How to make the gardenia leaves green and the flowers fragrant
The editor introduces you to the common topics of gardening knowledge about gardenias, how to make the gardenia leaves green and the flowers fragrant, with detailed introduction below.
Gardenias prefer warm and humid conditions, enjoy sunlight but are sensitive to intense sun exposure, can tolerate shade, are not very cold-resistant, with a growth temperature of 18-22°C, and can survive over winter at temperatures above 5°C, even enduring -5°C low temperatures. The biggest problem with caring for gardenias in the north is yellowing leaves, and sometimes when purchased, the plant may flower a lot but not bloom after a year of care.
This is because gardenias are very sensitive to soil pH, with the most suitable pH being 4.5-6. When the pH exceeds 6.5, yellowing leaves due to iron deficiency occur, as the soil and water in the north are alkaline. The pH of the potting soil at the time of purchase is relatively suitable, but due to continuous watering, the soil gradually becomes alkaline, and iron deficiency mainly manifests in the new leaves first, with the veins still green, and in severe cases, they turn yellowish-white with the leaf tips and edges becoming scorched. High temperatures, high humidity, intense sunlight, and poor ventilation can also cause lower leaves to yellow and fall off.
Winter frost damage or soil temperatures below 18°C during the growing period can also cause functional iron deficiency. Therefore, gardenias must be cultivated in well-drained, loose, and fertile sandy loam soil with a pH of 5-6. In the south, mountain or paddy soil is used, while in the north, a mixture of soil is prepared, usually 4 parts of decomposed leaf mold (peat), 4 parts of garden soil, 1 part of sand, and 1 part of manure, with 1-3 kilograms of sulfur or ferrous sulfate (or aluminum sulfate) added per 100 square meters. Watering must use alum fertilizer water, and the best way to prevent yellowing leaf disease is to mix organic fertilizer with ferrous sulfate.
Flower farmers use a mixture of grass compost and ferrous sulfate to effectively prevent yellowing leaf disease. In the summer, gardenias should be placed in a shaded greenhouse with good ventilation and higher humidity to prevent lower yellow leaves. Accumulation of water in the pot, frost damage to the roots in winter, and excessive fertilizer concentration can also cause yellow leaves, and these issues should be addressed promptly.
Gardenias enjoy fertilizer and can be fertilized with livestock manure or cake fertilizer water. During the growing season, apply alum fertilizer water every 10-15 days, add nitrogen and phosphorus fertilizers during the early spring budding period, and apply补充 fertilizers after flowering, usually with compound fertilizers. Gardenias enjoy moisture but dislike waterlogging, with watering every 2-3 days in spring and autumn, daily in summer, and every 5-7 days in winter. Watering must use 10-20 times the concentration of alum fertilizer water.
In the summer, spray water on the leaves in the morning and evening to make them glossy and green. After the spring, cut off the weak and long branches on the main stem, remove the remaining flowers after blooming, and when the branches grow to 10-20 centimeters, leave 2-3 pairs of leaves and pinch the top, adjusting the orientation of the branches to achieve moderate density and appropriate length. Gardenias have strong sprouting power, and if the canopy is too tall or dense, it can be thinned appropriately. After flowering, it can be pruned back in August, but should not be heavily pruned in winter.
Common diseases of gardenias include the T-J disease and leaf spot. In the early stages of the disease, it can be controlled with 75% carbendazim 600 times or 50% benomyl 800 times, applied every 7-10 days for 2-3 times. Leafhoppers and coffee clearwing moths can be controlled with 10% cypermethrin 3000 times.
The above sharing on how to make gardenia leaves green and the flowers fragrant is for reference by green plant enthusiasts, and it is hoped that it can solve your problems in green plant and flower management.