Effects of Substitute Substrate, Water, and Fertilizer Management on the Growth of Potted Chrysanthemums

: The chrysanthemum is a perennial herbaceous ﬂower with a long history of cultivation dating back over 3000 years. The potted chrysanthemum is a signiﬁcant type and is widely used in landscaping. Expensive substrate costs, complicated management of water and fertilizer, and uneven product quality currently plague the potted chrysanthemum industry. This study systematically investigated the growth status of potted chrysanthemums under different substrates, water, and fertilizer ratios and established a simpliﬁed cultivation system for potted chrysanthemums. The substitute substrate experiment demonstrated that coir: moss peat: perlite: pine needle mulch = 2:4:2:2 is the most suitable substitute substrate. Research on fertilizer ratios found that chrysanthemums’ best growth and ﬂowering characteristics were achieved with nitrogen, phosphorus, and potassium concentrations of 336 mg/L, 93 mg/L, and 273 mg/L, respectively. A comprehensive, simpliﬁed cultivation system was established when utilizing T4 substitute substrate (2:4:2:2 ratios of coir, moss peat, perlite, and pine needle mulch), 40% water capacity, and F9 fertilizer (336 mg/L nitrogen, 93 mg/L phosphorus, and 273 mg/L potassium). This study comprehensively and systematically explored the cultivation and maintenance schemes in the production of potted chrysanthemums and built a light, simple, and efﬁcient production technology system of potted chrysanthemums in the open ﬁeld suitable for the climatic characteristics of northern China, which provides feasible technical speciﬁcations and a theoretical basis for the reﬁnement and large-scale management of potted chrysanthemums. This experiment lays the foundations for cost reduction and efﬁciency in the potted chrysanthemum industry.


Introduction
Chrysanthemum is widely cultivated for ornamental purposes worldwide and has a long cultivation history [1].The potted chrysanthemum is popular in horticulture mainly because of its vivid colors, long flowering duration, and attractive rounded form [2]. Traditional cultivation technologies of potted chrysanthemums lack optimal dosages and ratios for potted chrysanthemums' unique needs [3].They also lack precision in resource management, leading to overuse or underutilization of inputs such as water, peat, and fertilizers.These problems seriously restrict the sustainability of potted chrysanthemum production [4,5].Recovered substrate (heap rot for one year) 100 T17 Recovered substrate (heap rot for two years) 100 Watering during cultivation was conducted before 10:00 every day according to weather conditions.Other cultivation management measures were treated the same except for the test conditions.
After potting, plants were watered once a day, and water-soluble fertilizer was applied once a week.We used LARRY (Wuhan Greencare Fertilizers Co., Ltd., Wuhan, China), a water-soluble fertilizer with a ratio of nitrogen, phosphorus, and potassium 20:10:20 in the growth period.

Experiments on Nitrogen-Phosphorus-Potassium Rationing
The fertilizer program including a control group (Clear water treatment) and LARRY fertilizer (water-soluble fertilizer commonly used in floriculture production, N: P: K = 20:10:20, Wuhan Greencare Fertilizers Co., Ltd., Wuhan, China) is shown in Table 2.It was applied using a three-factor, three-level, completely randomized group orthogonal experimental design.A total of 100 mL of the fertilizer solution was applied to each flower container once the fertilizer had been equally distributed and dissolved in the water.The concentration of the fertilizer was ascertained and converted into the appropriate mass.During fertilization, fertilizer was dissolved in water and placed evenly in pots, and 100 mL of fertilizer solution was added to each pot each time.Five pots, one seedling per pot, were treated by each treatment group.

Experiments on Substrate and Water-Fertilizer Rationing
The N3P3K2 (24 mmol/L N, 3.0 mmol/L P, and 7.0 mmol/L K, which was tested as the best NPK ratio through the experiment above) was chosen as the reference for this experiment.Three gradients of substrate treatments were referenced from our previous study, including the poor substrate combination (coir: perlite: pine needle mulch = 6:2:2), the best substrate combination (coir: moss peat: perlite: pine needle mulch = 2:4:2:2), and the substrate combination typically used in production.The percentage of saturated water capacity was used to express the three moisture treatments (W1, W2, and W3), and the weighing method was used to manage the moisture levels.Three concentration gradients of N3P3K2 (0.5×, 1×, and 1.5×) were established for fertilizer.The detailed experimental plan is shown in Table 3.The concentration of the fertilizer was ascertained and converted into the appropriate mass.During fertilization, fertilizer was dissolved in water and placed evenly in pots, and 100 mL of fertilizer solution was added to each pot each time.Three pots, one seedling per pot, were treated by each treatment group.

Measurement of Growth and Physiological Indices
After 80 days of cultivation, growth parameters including height, crown diameter, stem diameter, flower numbers, flower diameter, chlorophyll content, photosynthetic index, shoot dry weight, shoot fresh weight, total N, total P, and total K were measured.The detailed methods were adopted from a previous study [31][32][33].

Determination of Physical Properties of Substrates
The extracts were obtained by saturation extraction, pH was determined by a pH acidity meter (Potentiometric method), and EC values were determined by a DDS-307 conductivity meter.
A ring knife with a volume of 200 mL was used; the ring knife was weighed to W 0 mass, filled with a naturally dried mixed matrix, weighed as W 1 , and soaked in water for 24 h, weighed as W 2 .Soil bulk density and total porosity are calculated according to the following formula:

. Plant Height and Crown Width
A ruler was used to measure the height from the base of the chrysanthemum rhizome to the highest branch (accurate to 0.01 cm).

Photosynthetic Index
Measurements were made with a portable plant photosynthetic instrument (LI-6400, LI-COR Biosciences, Beijing, China).Three plants were selected for each treatment, three mature leaves in the middle and periphery of each plant were selected for measurement, and the average value was calculated.Assay times were 9-11 a.m.The net photosynthetic rate (Pn) (accurate to 0.001 µmol CO 2 /(m 2 •s)), transpiration rate (Tr) (accurate to 0.001 mmol H 2 O/(m 2 •s)), intercellular CO 2 concentration (Ci) (accurate to 0.001 µmol/mol), and stomatal conductance (Gs) (accurate to 0.001 mol H 2 O/(m 2 •s)) were measured.

Flower Diameter
When the potted chrysanthemum was in full bloom, the largest flower diameter was measured using vernier calipers; 3 plants were selected for each treatment, five flowers were taken from each plant to measure, and the average value was calculated (accurate to 0.01 mm).

Determination of Fresh and Dry Weight of Shoots
The chrysanthemums were cut from the rhizomes, and the above-ground parts were kept and weighed with an electronic balance to determine the fresh weight (accurate to 0.01 g).Then, they were put in an oven at 120 • C for 30 min, dried at 80 • C to constant weight, and weighed with an electronic balance to determine the dry weight (accurate to 0.01 g).

Analysis of Plant Nutrients
Plant samples were crushed into a powder in a grinder for biomass analysis, and the powder was subsequently filtered through a sieve with a mesh size of 100.H 2 SO 4 -H 2 O 2 was used to filter the abrasive material (0.2 g).The total nitrogen concentration was ascertained using the Kjeldahl nitrogen determination method and the KDY-9820 automatic nitrogen ion meter.The molybdenum phosphate yellow technique and the UV-2550 UV-Vis spectrophotometer were used to calculate the total phosphorus concentrations.SpectraAA220 atomic absorption spectrometry was used to measure total K concentrations.

Statistical Analysis
One-way analysis of variance (ANOVA) and principal component analysis (PCA) were performed using SPSS 21.0, containing all the indices, and multiple comparisons were performed using Duncan's test for significant differences (p < 0.05).The results were plotted using GraphPad Prism 8.  4 displays the physicochemical characteristics of several substitute substrates.The recovery matrix T17 group had the highest bulk density, while the coir matrix T6 group had the lowest.In contrast to the CK group, the bulk density of the substrate entirely substituted with bark (T9), rice husk (T12), and fungal residue (T15) increased, whereas the bulk density of the substrate substituted with peanut shell (T3) and coir (T6) decreased.Regarding total porosity, coir substrate T6 had the most extensive total porosity, and recovered matrix T16 had the most minor total porosity.The substitute substrate group of peanut shell (T1, T2, T3) and coir (T4, T5, T6) increased compared with the CK group.In contrast, the substitute substrate group of bark (T7, T8, T9), rice husk (T10, T11, T12), and fungal residue (T13, T14, T15) decreased compared with the control group.Regarding the EC value, the EC value of the T12 group was the highest, while that of the T17 group was the most minor.The recovery substrates (T16, T17) decreased compared with the control group, and the rest increased.In terms of pH value, the pH value of T10 was the smallest, while that of T17 was the largest, the substitute substrate group of rice husk (T10, T11, T12) was acidic, and the other groups were neutral or weakly alkaline.The T17 treatment group was alkaline, and the other groups were within the appropriate range.The total nitrogen content was the highest in CK, followed by the T3 substitute substrate, and the lowest in the T6 substitute substrate.The entire nitrogen content of the substitute substrate group of peanut shells (T1, T2, T3) and rice husks (T11, T12, T13) was higher than the rest.The total nitrogen content decreased with the decrease in peat in all substitute substrate groups.The entire phosphorus content was the highest in the T12 substitute substrate and the lowest in the T8 substitute substrate.The total potassium content was the highest in the T6 substitute substrate and the weakest in T3.The total phosphorus content increased as the peat decreased in all substitute substrate groups.The organic carbon content was the highest in CK and the lowest in T15.As the moss peat content decreased, the organic carbon content in all substrates decreased.

Effects of Substitute Substrates on Growth Indices of C. morifolium 'Hanluqiushi'
The plants' growth indices of 'Hanluqiushi' under various circumstances are shown in Table 5. Gradually rising fertility was accompanied by progressive plant height and crown diameter increases.At 80 days of cultivation, the plant height of the potted chrysanthemum treated with traditional cultivation substrate CK was 16.47 cm, and the highest plant height was 18.87 cm in the T4 treatment group, which was significantly 114.6% higher than that of the CK group.The lowest was 8.87 cm in the T6 treatment group, significantly different from the CK group.In terms of crown diameter, the crown width of the CK group was 26.5 cm.The crown width of the T4 treatment group was the largest, 27.73 cm, 104.6% larger than that of the CK group.The T17 treatment group had the smallest crown width, 16.67 cm, significantly smaller than the CK group.

Effects of Substitute Substrates on Physiological Indices of C. morifolium 'Hanluqiushi'
As is shown in Figure 1a-d, different treatments affected the photosynthetic indexes of 'Hanluqiushi'.Regarding the net photosynthetic rate, the CK group had the highest photosynthetic rate, while the T17 treatment group had the lowest, significantly different from the CK group.Moreover, the stomatal conductance was the highest in the T2 treatment group and the smallest in the T10 treatment group.Regarding intercellular carbon dioxide concentration, the T17 treatment group was the highest and the T8 treatment group was the lowest, while the transpiration rate was the highest in the T10 treatment group and the lowest in the T6 treatment group.
As is shown in Figure 2, significant differences existed in the fresh and dry weight of shoots of chrysanthemum cultivated in different substrate treatment groups (p < 0.05).The fresh weight of the shoots in the CK treatment group was 241.9 g.The T8 treatment group had the most significant fresh weight, which was 284.48 g, an increase of 117.6% compared with the CK group, while the T17 group, which was the most minor (48.21 g) was 80.1% lower than that of the CK group.The fresh weight of the T8 and T4 treatment groups was significantly higher than that of the CK group.Regarding dry weight, the dry weight of the shoots of the CK treatment group was 52.7 g.Among the treatment groups, the dry weight of the T7 treatment group was the largest, reaching 54.68 g, which was 103.7% higher than that of the CK group, while the dry weight of the T17 treatment group was the smallest at 8.63 g, 83.6% lower than that of the CK group.
es of 'Hanluqiushi'.Regarding the net photosynthetic rate, the CK group had the h photosynthetic rate, while the T17 treatment group had the lowest, significantly d ent from the CK group.Moreover, the stomatal conductance was the highest in t treatment group and the smallest in the T10 treatment group.Regarding interce carbon dioxide concentration, the T17 treatment group was the highest and t treatment group was the lowest, while the transpiration rate was the highest in th treatment group and the lowest in the T6 treatment group.As is shown in Figure 2, significant differences existed in the fresh and dry weight of shoots of chrysanthemum cultivated in different substrate treatment groups (p < 0.05).The fresh weight of the shoots in the CK treatment group was 241.9 g.The T8 treatment group had the most significant fresh weight, which was 284.48 g, an increase of 117.6% compared with the CK group, while the T17 group, which was the most minor (48.21 g) was 80.1% lower than that of the CK group.The fresh weight of the T8 and T4 treatment groups was significantly higher than that of the CK group.Regarding dry weight, the dry weight of the shoots of the CK treatment group was 52.7 g.Among the treatment groups, the dry weight of the T7 treatment group was the largest, reaching 54.68 g, which was 103.7% higher than that of the CK group, while the dry weight of the T17 treatment group was the smallest at 8.63 g, 83.6% lower than that of the CK group.As is shown in Figures 3 and 4, during the entire flowering period of 'Hanluqiushi', the chrysanthemum growth of the T6 and T17 treatment groups was significantly weaker than that of the CK group, and the T17 treatment group was the weakest.Significant

Effects of Substitute Substrates on Blooming Indices of C. morifolium 'Hanluqiushi'
As is shown in Figures 3 and 4, during the entire flowering period of 'Hanluqiushi', the chrysanthemum growth of the T6 and T17 treatment groups was significantly weaker than that of the CK group, and the T17 treatment group was the weakest.Significant differences existed in the 'Hanluqiushi' flower diameter cultivated with the different substrates (p < 0.05).The flower diameter of the CK group was 48.88 mm, while that of the T4 treatment group was the largest (52.37 mm), which was 7.1% higher than that of the control group.The flower diameter of the T16 treatment group was the smallest (36.38 mm), which was 25.6% smaller than that of the control group.

Comprehensive Evaluation of Substitute Substrates
According to the Figure 5, nine indicators for potted chrysanthemums with various nitrogen, phosphorus, and potassium ratios were evaluated using principal component analysis (PCA).Three significant components, accounting for 89.26% of the total variance, were retrieved.Principal component scores (F) and growth indicators were shown to be related.Table 6 presents the final scoring formulas for each principal component.Chrysanthemum growth was evaluated thoroughly using composite ratings (F).The score for treatment group T4 (coir: moss peat: perlite: pine needle soil = 2:4:2:2) was 1.27, followed by T5 (coir: moss peat: perlite: pine needle soil = 4:2:2:2) with 1.20, while the control group CK came in seventh overall with a score of 0.23.Using this analysis, the best substitute substrate can be chosen for improved chrysanthemum production, shown in Table 7.According to the integrated evaluation of the principal component analysis, the combined performance of the T4 treatment group was significantly better than that of the CK and the T4 treatment groups (coir: moss peat: perlite: pine needle soil = 2:4:2:2) was the best substitute substrate under the traditional cultivation substrate conditions.

Comprehensive Evaluation of Substitute Substrates
According to the Figure 5, nine indicators for potted chrysanthemums with various nitrogen, phosphorus, and potassium ratios were evaluated using principal component analysis (PCA).Three significant components, accounting for 89.26% of the total variance, were retrieved.Principal component scores (F) and growth indicators were shown to be related.Table 6 presents the final scoring formulas for each principal component.Chrysanthemum growth was evaluated thoroughly using composite ratings (F).The score for treatment group T4 (coir: moss peat: perlite: pine needle soil = 2:4:2:2) was 1.27, followed by T5 (coir: moss peat: perlite: pine needle soil = 4:2:2:2) with 1.20, while the control group CK came in seventh overall with a score of 0.23.Using this analysis, the best substitute substrate can be chosen for improved chrysanthemum production, shown in Table 7.According to the integrated evaluation of the principal component analysis, the combined performance of the T4 treatment group was significantly better than that of the CK and the T4 treatment groups (coir: moss peat: perlite: pine needle soil = 2:4:2:2) was the best substitute substrate under the traditional cultivation substrate conditions.

Comprehensive Evaluation of Substitute Substrates
According to the Figure 5, nine indicators for potted chrysanthemums with various nitrogen, phosphorus, and potassium ratios were evaluated using principal component analysis (PCA).Three significant components, accounting for 89.26% of the total variance, were retrieved.Principal component scores (F) and growth indicators were shown to be related.Table 6 presents the final scoring formulas for each principal component.Chrysanthemum growth was evaluated thoroughly using composite ratings (F).The score for treatment group T4 (coir: moss peat: perlite: pine needle soil = 2:4:2:2) was 1.27, followed by T5 (coir: moss peat: perlite: pine needle soil = 4:2:2:2) with 1.20, while the control group CK came in seventh overall with a score of 0.23.Using this analysis, the best substitute substrate can be chosen for improved chrysanthemum production, shown in Table 7.According to the integrated evaluation of the principal component analysis, the combined performance of the T4 treatment group was significantly better than that of the CK and the T4 treatment groups (coir: moss peat: perlite: pine needle soil = 2:4:2:2) was the best substitute substrate under the traditional cultivation substrate conditions.The plants' growth indices of 'Hanluqiushi' under various circumstances are shown in Table 8.Gradually rising fertility was accompanied by progressive increases in plant height, crown diameter, and stem diameter.The fertilizer level influenced the substantial difference in plant height across treatments (p < 0.05).At day 80, the plants in the LR, F3, and F6 treatment groups were the tallest, the LR and F9 treatment groups had the largest crown diameter, and the F9 treatment group had the thickest stems.

Effects of Nitrogen, Phosphorus, and Potassium Ratios on Physiological Indices of C. morifolium 'Hanluqiushi'
To assess the effects of different fertilizer treatments on potted chrysanthemums, we focused on comparing the biomass, chlorophyll content, and nutrient content of the whole plant at the 80 days of cultivation (Figures 6 and 7).Significant interactions between different ratio treatments and organs were observed, greatly influencing the nutrient content (p < 0.05).The shoot fresh weight of the aerial parts in the CK treatment group was 14.76 g.The F9 treatment group had the highest fresh weight of 52.29 g, 354.27% higher than the control group.The dry weight of the aerial parts of the CK treatment group was 3.38 g.The maximum dry weight of the F4 treatment group was 12.60 g, which was 372.78% higher than that of the control group, and the CK dry weight was the lowest in the control group.The F9 treatment group had the most incredible chlorophyll content (118.28% of CK).
Regarding the total nitrogen (TN) content and total phosphorus (TP) content, the TN content ranged between 2.99 to 44.37 g•100 g −1 , while the F9 treatment group had the highest TN content.Although variations in the TP content were negligible, fertilization significantly increased the TP content of all plants.The F6 treatment group exhibited the highest increase in TP content (222.48% of CK).For the total potassium (TK) content, all treatment groups showed a significant deviation from the CK.The LR and F9 treatment groups had the highest TK content (221.74% and 216.60% of CK, respectively).Regarding the total nitrogen (TN) content and total phosphorus (TP) content, TN content ranged between 2.99 to 44.37 g•100 g −1 , while the F9 treatment group had highest TN content.Although variations in the TP content were negligible, fertiliza significantly increased the TP content of all plants.The F6 treatment group exhibited highest increase in TP content (222.48% of CK).For the total potassium (TK) content treatment groups showed a significant deviation from the CK.The LR and F9 treatm groups had the highest TK content (221.74% and 216.60% of CK, respectively).As is shown in Figures 8 and 9, regarding the number of flowers, the X9 group had the most, 172.80, while the CK group had the fewest, 41.80.Concerning flower diameter, the X5 group had the biggest (55.16 mm), while the CK group had the smallest (43.94 mm).
significantly increased the TP content of all plants.The F6 treatment group exhibit highest increase in TP content (222.48% of CK).For the total potassium (TK) conte treatment groups showed a significant deviation from the CK.The LR and F9 trea groups had the highest TK content (221.74% and 216.60% of CK, respectively).

Effects of Nitrogen, Phosphorus, and Potassium Ratios on Flower Qualities of morifolium 'Hanluqiushi'
As is shown in Figures 8 and 9, regarding the number of flowers, the X9 grou the most, 172.80, while the CK group had the fewest, 41.80.Concerning flower diam the X5 group had the biggest (55.16 mm), while the CK group had the smallest mm).

Comprehensive Evaluation of Nitrogen, Phosphorus, and Potassium Fertilizer Rationing
As shown in Figure 10, eleven indicators for potted chrysanthemums with various nitrogen, phosphorus, and potassium ratios were evaluated using principal component analysis (PCA).Four significant components, accounting for 85.25% of the total variance, were retrieved.Principal component scores (F) and growth indicators were shown to be related.Table 9 presents the final scoring formulas for each principal component.Chrysanthemum growth was evaluated thoroughly using composite ratings (F).The score for treatment group X9 (N3 P3 K2) was 0.83, was followed by LR with 0.72, while the control group CK came in eleventh overall with a score of 0.19.With use of this analysis, the best nutrient ratios can be chosen for improved chrysanthemum production, as shown in Table 10.According to the integrated evaluation of the principal component analysis, the combined performance of the X9 treatment group was significantly better than that of the CK and LR, and the X9 treatment group (N3 P3 K2) was the best NPK fertilizer program under the traditional cultivation substrate conditions.

Comprehensive Evaluation of Nitrogen, Phosphorus, and Potassium Fertilizer Rationing
As shown in Figure 10, eleven indicators for potted chrysanthemums with various nitrogen, phosphorus, and potassium ratios were evaluated using principal component analysis (PCA).Four significant components, accounting for 85.25% of the total variance, were retrieved.Principal component scores (F) and growth indicators were shown to be related.Table 9 presents the final scoring formulas for each principal component.Chrysanthemum growth was evaluated thoroughly using composite ratings (F).The score for treatment group X9 (N3 P3 K2) was 0.83, was followed by LR with 0.72, while the control group CK came in eleventh overall with a score of 0.19.With use of this analysis, the best nutrient ratios can be chosen for improved chrysanthemum production, as shown in Table 10.According to the integrated evaluation of the principal component analysis, the combined performance of the X9 treatment group was significantly better than that of the CK and LR, and the X9 treatment group (N3 P3 K2) was the best NPK fertilizer program under the traditional cultivation substrate conditions.related.Table 9 presents the final scoring formulas for each principal component.Chrysanthemum growth was evaluated thoroughly using composite ratings (F).The score for treatment group X9 (N3 P3 K2) was 0.83, was followed by LR with 0.72, while the control group CK came in eleventh overall with a score of 0.19.With use of this analysis, the best nutrient ratios can be chosen for improved chrysanthemum production, as shown in Table 10.According to the integrated evaluation of the principal component analysis, the combined performance of the X9 treatment group was significantly better than that of the CK and LR, and the X9 treatment group (N3 P3 K2) was the best NPK fertilizer program under the traditional cultivation substrate conditions.Table 9. Final score formula for the three principal components of nitrogen, phosphorus, and potassium fertilizer rationing.

Principal Component
Score Formula 1 Y = 0.104X  The plants' growth indices of 'Hanluqiushi' under various circumstances are shown in Table 11.Gradually rising fertility was accompanied by progressive plant height, crown diameter, and stem diameter increases.The fertilizer level influenced the substantial difference in plant height across treatments (p < 0.05).At day 80, the plants in the W1, W5, and W6 treatment groups were the tallest, the W6 treatment group had the largest crown diameter, and the W2, W4, and W6 treatment groups had the thickest stems.

Effect of Substrate, Water, and Fertilizer Ratio on the Physiological Indices of C. morifolium 'Hanluqiushi'
To assess the effects of different fertilizer treatments on potted chrysanthemums, we focused on comparing the biomass, chlorophyll content, and nutrient content of the whole plant at the 80 days of cultivation (Figures 11 and 12).Significant interactions between different ratio treatments and organs were observed, greatly influencing the nutrient content (p < 0.05).The shoot fresh weight of the aerial parts in the W1 treatment group was 24.55 g.The W4 treatment group had the highest fresh weight of 43.01 g, 175.19% higher than the control group.The dry weight of the aerial parts of the W1 treatment group was 5.78 g.The maximum dry weight of the W6 treatment group was 7.56 g, which was 130.80% higher than that of the control group, and the CK dry weight was the lowest in the control group.The W6 treatment group had the most incredible chlorophyll content (126.84% of CK).
Regarding the total nitrogen (TN) content and total phosphorus (TP) content, the TN content ranged between 2.95 to 4.10 g•100 g −1 , while the W2 treatment group had the highest TN content.Although variations in the TP content were negligible, fertilization significantly increased the TP content of all plants.The W7 treatment group exhibited the highest increase in TP content (119.72% of W1).For the total potassium (TK) content, the W9 treatment group had the highest TK content (101.62% of W1).To assess the effects of different fertilizer treatments on potted chrysanthemums, we focused on comparing the biomass, chlorophyll content, and nutrient content of the whole plant at the 80 days of cultivation (Figures 11 and 12).Significant interactions between different ratio treatments and organs were observed, greatly influencing the nutrient content (p < 0.05).The shoot fresh weight of the aerial parts in the W1 treatment group was 24.55 g.The W4 treatment group had the highest fresh weight of 43.01 g, 175.19% higher than the control group.The dry weight of the aerial parts of the W1 treatment group was 5.78 g.The maximum dry weight of the W6 treatment group was 7.56 g, which was 130.80% higher than that of the control group, and the CK dry weight was the lowest in the control group.The W6 treatment group had the most incredible chlorophyll content (126.84% of CK).Regarding the total nitrogen (TN) content and total phosphorus (TP) content, the TN content ranged between 2.95 to 4.10 g•100 g −1 , while the W2 treatment group had the highest TN content.Although variations in the TP content were negligible, fertilization significantly increased the TP content of all plants.The W7 treatment group exhibited the highest increase in TP content (119.72% of W1).For the total potassium (TK) content, the W9 treatment group had the highest TK content (101.62% of W1).

Effects of Substrate, Water, and Fertilizer Ratio on Flower Qualities of C. morifolium 'Hanluqiushi'
As is shown in Figures 13 and 14, regarding the number of flowers, the W4 group had the most (159.30),while the W7 group had the fewest (56.33).Concerning flower diameter, the W6 group had the biggest (52.67 mm), while the W8 group had the smallest (38.73 mm).As is shown in Figures 13 and 14, regarding the number of flowers, the W4 group had the most (159.30),while the W7 group had the fewest (56.33).Concerning flower diameter, the W6 group had the biggest (52.67 mm), while the W8 group had the smallest (38.73 mm).
TN content ranged between 2.95 to 4.10 g•100 g −1 , while the W2 treatment group ha highest TN content.Although variations in the TP content were negligible, fertiliz significantly increased the TP content of all plants.The W7 treatment group exhi the highest increase in TP content (119.72% of W1).For the total potassium (TK) con the W9 treatment group had the highest TK content (101.62% of W1).As is shown in Figures 13 and 14, regarding the number of flowers, the W4 g had the most (159.30),while the W7 group had the fewest (56.33).Concerning flowe ameter, the W6 group had the biggest (52.67 mm), while the W8 group had the sma (38.73 mm).

Integrated Evaluation of Substrate and Water Fertilization
As is shown in Figure 15, eleven indicators for potted chrysanthemums with various nitrogen, phosphorus, and potassium ratios were evaluated using principal component analysis (PCA).Four significant components, accounting for 89.25% of the total variance, were retrieved.Principal component scores (F) and growth indicators were shown to be related.Table 12 presents the final scoring formulas for each principal component.Chry-santhemum growth was evaluated thoroughly using composite ratings (F).The score for treatment group W6 was 0.69, followed by W4 with 0.66, while W7 came in ninth with a score of 0.21.With use of this analysis, the best substrate and water fertilization can be chosen for improved chrysanthemum production, as shown in Table 13.According to the integrated evaluation of the principal component analysis, the combined performance of the W6 treatment group was significantly better than that of the others, and the W6 treat-ment group was the best substrate and water fertilization under the traditional cultivation substrate conditions.

Integrated Evaluation of Substrate and Water Fertilization
As is shown in Figure 15, eleven indicators for potted chrysanthemums with various nitrogen, phosphorus, and potassium ratios were evaluated using principal component analysis (PCA).Four significant components, accounting for 89.25% of the total variance, were retrieved.Principal component scores (F) and growth indicators were shown to be related.Table 12 presents the final scoring formulas for each principal component.Chrysanthemum growth was evaluated thoroughly using composite ratings (F).The score for treatment group W6 was 0.69, followed by W4 with 0.66, while W7 came in ninth with a score of 0.21.With use of this analysis, the best substrate and water fertilization can be chosen for improved chrysanthemum production, as shown in Table 13.According to the integrated evaluation of the principal component analysis, the combined performance of the W6 treatment group was significantly better than that of the others, and the W6 treatment group was the best substrate and water fertilization under the traditional cultivation substrate conditions.

Discussion
Simplified cultivation in ornamental plants, including Pelargonium hortorum, Cyclamen persicum [34], Euphorbia pulcherrima [35], etc., has been reported in the literature.Chrysanthemum morifolium, one of the top ten cut flowers and one of the most popular potted flowers in the international market, is widely used in landscaping [21].Currently, China's potted chrysanthemum industry suffers from problems of high substrate cost, sloppy water and fertilizer management, uneven quality of potted flowers, a severe mismatch between the scale of the industry and existing industrial or technological innovations, etc.Therefore, applying simplified cultivation in the potted chrysanthemum industry is necessary.
In soilless culture, the substrate is the medium for plant growth, providing water, fertilizer, and an excellent inter-root environment; its physicochemical properties are closely related to plant growth and development, and it helps to reduce soil-related problems in conventional crop cultivation [22].Moss peat is currently the most commonly used substrate for soilless culture.However, due to the high environmental damage associated with its acquisition, there is a need to develop new and excellent soilless substrates to replace moss peat in its application.A few of the more prevalent alternatives to substrates are rice husk, bark [36], coir [37], and compost [38].It has been discovered that most of the impact requirements for Pelargonium hortorum could be met by raising the compost content to 40%, reducing the need for chemical fertilizers [34].To grow Gerbera jamesonii, compost and coir can be mixed together as a culture substrate instead of peat [39].Compared to regular imported peat, Anthurium andraeanum can flower at its best when a portion of moss peat is replaced with rotten rice husks and agroforestry wastes [40], which can also be applied as a substitute substrate in production [41].In this experiment, nine indicators of potted chrysanthemums were combined by principal component analysis to evaluate 18 substrates.The results showed that the T4 treatment group (coir: moss peat: perlite: pine needle soil = 2:4:2:2) was the best, which was consistent with the results of Xiong et al. [38] and Riaz et al. [39].
Different N, P, and K fertilizer applications have a significant impact on the physiological indices of Machilus chinensis seedlings [42]; the use of N: P: K = 2: 3: 2 fertilizers in chrysanthemum cultivation resulted in the best performance of chrysanthemums in photosynthetic shape and flowering traits [43].Appropriate N, P, and K fertilization increased plant height, crown spread, diameter, and total biomass of seedlings [41], which agrees with the present study's findings.The present study found that chrysanthemum growth was significantly better than CK after fertilizer application.The F9 treatment group was superior to CK and LR used in general flower production with an F value of 0.83, which was ranked first overall.Nitrogen is an essential nutrient for plant growth and photosynthesis [43].In this experiment, plant height, crown width, and stem thickness increased significantly with nitrogen concentration.Consistent with the previous study's findings, potash is an essential nutrient for plant protein, transpiration, respiration, and chlorophyll production, and is also necessary to improve the flower traits of flower crops [42].In the present study, the plants' chlorophyll content and flower size also increased with the increase in potassium content, which agrees with previous studies findings.Therefore, using 336 mg/L nitrogen, 93 mg/L phosphorus, and 273 mg/L potassium, as seen in the F9 treatment group, can be considered an ideal NPK fertilizer in conventional cultivation substrates.
In this experiment, the S6 treatment group using 40% water holding capacity, N3P3K2 fertilizer had the most significant plant height and crown diameter, the largest flower diameter, and the highest number of flower heads, which indicates that 40% water holding capacity is beneficial to the growth of plant height and crown size of potted chrysanthemum.On the other hand, S4 treated with N3P3K2 fertilizer had the highest fresh and dry weight, while plants treated with 1.5 times N3P3K2 fertilizer concentration showed a decrease in all indicators.This indicates that the appropriate increase in fertilizer concentration can achieve the effect of increased yield, and too high fertilizer concentration will instead inhibit the growth of plants, which is consistent with the results of previous studies [44].
Through the screening of substitute substrates, the screening of nitrogen, phosphorus, and potassium ratios, and the screening of substrate water and fertilizer formulas, this study comprehensively and systematically explored the cultivation and maintenance schemes in the production of potted chrysanthemums and built a light, simple, and efficient production technology system for potted chrysanthemums in an open field that is suitable for the climatic characteristics of northern China, providing feasible technical specifications and a theoretical basis for the refinement and large-scale management of potted chrysanthemums.However, this study only used the chrysanthemum quality 'Hanluqiushi' as the experimental material; thus, more data are needed for the whole chrysanthemum cultivation industry.In addition, the cultivation time was half a month later than the critical time of chrysanthemum production, which resulted in the overall growth of the subsequent chrysanthemums being weaker than that of actual production.Therefore, it is recommended that future trials are conducted for more cultivars at the appropriate production time to verify the cultivation effect of the substitute substrate and water and fertilizer formulations.
Last but not least, the production of chrysanthemums in pots with the ideal ratios of water holding capacity (40%), fertilizer (N3P3K2), and substrate (coir: moss peat: perlite: pine needle soil = 2:4:2:2) produced a production cost of RMB 2.64/m 3 , 16.4% less than that of the CK group (with a production cost of RMB 3.28/m 3 ).

Conclusions
This study aimed to enhance the quality and efficiency of potted chrysanthemum production in China.The substitute substrate experiment demonstrated that coir: moss peat: perlite: pine needle mulch = 2:4:2:2 is the most suitable substitute substrate among others.Through research on fertilizer ratios, it was found that the best growth and flowering characteristics of chrysanthemums were achieved with nitrogen, phosphorus, and potassium concentrations of 336 mg/L, 93 mg/L, and 273 mg/L, respectively.The substrate-waterfertilizer coupling experiment demonstrated that utilizing a 2:4:2:2 ratio of coir, moss peat, perlite, and pine needle mulch, along with 40% water capacity, and 336 mg/L nitrogen, 93 mg/L phosphorus, and 273 mg/L potassium led to improved chrysanthemum behavior.In addition, production costs are reduced by 16.4% with the use of new water, fertilizer and substrate management.These findings provide valuable insights for optimizing potted chrysanthemum cultivation practices.

Figure 2 .
Figure 2. Effect of substitute substrates on the biomass of potted chrysanthemums.The vertical coordinate represents the weight (g).The horizontal coordinates represent the 18 treatment groups CK, T1-T17.Data are mean ± standard error (n = 3).Different lowercase letters indicate significant differences (p < 0.05), as determined by Duncan's multiple range test.3.1.4.Effects of Substitute Substrates on Blooming Indices of C. morifolium 'Hanluqiushi'

Figure 2 .
Figure 2. Effect of substitute substrates on the biomass of potted chrysanthemums.The vertical coordinate represents the weight (g).The horizontal coordinates represent the 18 treatment groups CK, T1-T17.Data are mean ± standard error (n = 3).Different lowercase letters indicate significant differences (p < 0.05), as determined by Duncan's multiple range test.

24 Figure 3 .
Figure 3.Effect of substitute substrates on the flower diameter of potted chrysanthemums.The vertical coordinate represents the flower diameter (mm).The horizontal coordinates represent the 18 treatment groups CK, T1-T17.Different lowercase letters indicate significant differences (p < 0.05), as determined by Duncan's multiple range test.

Figure 4 .
Figure 4. Effect of substitute substrates on the flower quality of potted chrysanthemums.

Figure 3 . 24 Figure 3 .
Figure 3.Effect of substitute substrates on the flower diameter of potted chrysanthemums.The vertical coordinate represents the flower diameter (mm).The horizontal coordinates represent the 18 treatment groups CK, T1-T17.Different lowercase letters indicate significant differences (p < 0.05), as determined by Duncan's multiple range test.

Figure 4 .
Figure 4. Effect of substitute substrates on the flower quality of potted chrysanthemums.

Figure 4 .
Figure 4. Effect of substitute substrates on the flower quality of potted chrysanthemums.

Figure 5 .
Figure 5. Principal component analysis for substitute substrates.

Figure 5 .
Figure 5. Principal component analysis for substitute substrates.

Figure 7 .
Figure 7. Effect of nitrogen, phosphorus, and potassium ratio on the biomass of potted chry themums.The horizontal coordinates represent the 11 treatment groups (CK, LR, and F1-F9).D are mean ± standard error (n = 5).Different lowercase letters indicate significant differences 0.05), as determined by Duncan's multiple range test.

3. 2 . 3 .
Effects of Nitrogen, Phosphorus, and Potassium Ratios on Flower Qualities of C

Figure 7 .
Figure 7. Effect of nitrogen, phosphorus, and potassium ratio on the biomass of potted chrysanthemums.The horizontal coordinates represent the 11 treatment groups (CK, LR, and F1-F9).Data are mean ± standard error (n = 5).Different lowercase letters indicate significant differences (p < 0.05), as determined by Duncan's multiple range test.

Figure 8 .
Figure 8.Effect of nitrogen, phosphorus, and potassium ratio on the flowering number and d ter of potted chrysanthemums: (a) Flower diameter (mm); (b) Flower number.The horizon ordinates represent the 11 treatment groups (CK, LR, and F1-F9).Data are mean ± standard (n = 5).Different lowercase letters indicate significant differences (p< 0.05), as determined by can's multiple range test.

Figure 8 .
Figure 8.Effect of nitrogen, phosphorus, and potassium ratio on the flowering number and diameter of potted chrysanthemums: (a) Flower diameter (mm); (b) Flower number.The horizontal coordinates represent the 11 treatment groups (CK, LR, and F1-F9).Data are mean ± standard error (n = 5).Different lowercase letters indicate significant differences (p< 0.05), as determined by Duncan's multiple range test.Horticulturae 2024, 10, x FOR PEER REVIEW 15 of 24

Figure 9 .
Figure 9.Effect of nitrogen, phosphorus, and potassium ratio on the flowering quality of potted chrysanthemums.

Figure 9 .
Figure 9.Effect of nitrogen, phosphorus, and potassium ratio on the flowering quality of potted chrysanthemums.

Figure 10 .
Figure 10.Principal component analysis for nitrogen, phosphorus, and potassium fertilizer rationing.(a) PCA between CK and other treatments; (b) PCA between different treatments.Figure 10.Principal component analysis for nitrogen, phosphorus, and potassium fertilizer ration-ing.(a) PCA between CK and other treatments; (b) PCA between different treatments.

Figure 10 .
Figure 10.Principal component analysis for nitrogen, phosphorus, and potassium fertilizer rationing.(a) PCA between CK and other treatments; (b) PCA between different treatments.Figure 10.Principal component analysis for nitrogen, phosphorus, and potassium fertilizer ration-ing.(a) PCA between CK and other treatments; (b) PCA between different treatments.

Figure 12 .
Figure 12.Effect of substrate, water, and fertilizer on the biomass of potted chrysanthemums.The horizontal coordinate represents the 9 treatment groups (W1-W9).Data are mean ± standard error (n = 3).Different lowercase letters indicate significant differences (p < 0.05), as determined by Duncan's multiple range test.

Figure 12 .
Figure 12.Effect of substrate, water, and fertilizer on the biomass of potted chrysanthemums.The horizontal coordinate represents the 9 treatment groups (W1-W9).Data are mean ± standard error (n = 3).Different lowercase letters indicate significant differences (p < 0.05), as determined by Duncan's multiple range test.

Figure 13 .
Figure 13.Effect of substrate, water, and fertilizer on the flower diameter and number of p chrysanthemums: (a) Flower diameter (mm); (b) Flower number.The horizontal coordi Figure 13.Effect of substrate, water, and fertilizer on the flower diameter and number of potted chrysanthemums: (a) Flower diameter (mm); (b) Flower number.The horizontal coordinates represent the 9 treatment groups (W1-W9).Data are mean ± standard error (n = 3).Different lowercase letters indicate significant differences (p < 0.05), as determined by Duncan's multiple range test.Horticulturae 2024, 10, x FOR PEER REVIEW 19 of 24

Figure 14 .
Figure 14.Effect of substrate, water, and fertilizer on the flower quality and number of potted chrysanthemums.

Figure 14 .
Figure 14.Effect of substrate, water, and fertilizer on the flower quality and number of potted chrysanthemums.

Figure 15 .
Figure 15.Principal component analysis for substrate and water fertilization.

Figure 15 .
Figure 15.Principal component analysis for substrate and water fertilization.

Table 1 .
Cultivation experiment plan with different substrates.

Table 3 .
Substrate and water fertilizer combination test plan.

Table 4 .
Physicochemical properties of different substrates.

Table 5 .
Effects of substitute substrates on the height and crown diameter of potted chrysanthemum.

Table 7 .
Comprehensive evaluation of substitute substrates.

Table 7 .
Comprehensive evaluation of substitute substrates.Effects of Nitrogen, Phosphorus, and Potassium Ratios on the Growth and Physiological Indices of Potted Chrysanthemum 3.2.1.Effects of Nitrogen, Phosphorus, and Potassium Ratios on C. morifolium 'Hanluqiushi' Growth Indices

Table 8 .
Effects of nitrogen, phosphorus, and potassium ratios on the growth indices of potted chrysanthemum.

Table 10 .
Comprehensive evaluation of nitrogen, phosphorus, and potassium fertilizer rationing.Effects of Substrate, Water, and Fertilizer Ratio on the Growth and Physiological Indices of Potted Chrysanthemum 3.3.1.Effect of Substrate, Water, and Fertilizer Ratio on the Growth Indices of C. morifolium 'Hanluqiushi'

Table 11 .
Effects of substrate, water, and fertilizer on the growth indices of potted chrysanthemum.Data are mean ± standard error (n = 3); different lowercase letters indicate significant differences (p < 0.05).3.3.3.Effects of Substrate, Water, and Fertilizer Ratio on Flower Qualities of C. morifolium 'Hanluqiushi'

Table 13 .
Comprehensive evaluation of substrate and water fertilization.

Table 13 .
Comprehensive evaluation of substrate and water fertilization.