How to grow white magnolia? Master these care tips
1. Understand the living environment white magnolia needs. White magnolia likes warmth and humidity, prefers good ventilation and ample sunlight, fears cold, avoids dampness, and neither likes shade nor tolerates sunscald. It seems its requirements are quite high, so we need to take extra care of it.
2. Watering white magnolia is a very skillful task. Watering is the key to growing white magnolia well, but because its roots are fleshy, it fears waterlogging and cannot tolerate drought. In spring, when it is moved outdoors, water it thoroughly once, then water thoroughly once every other day; in summer, water once in the morning and once in the evening, and in extremely dry conditions spray water on the leaves; in autumn, water once every 2-3 days; in winter, reduce watering, as long as the potting soil is slightly moist; after rain, promptly pour off accumulated water. Apply light fertilizer frequently, preferably cake fertilizer; do not fertilize in winter; from after new buds sprout until June, apply liquid fertilizer once every 3-4 days; from July to September, apply liquid fertilizer once every 5-6 days; after applying fertilizer several times, stop once.
3. Soil cannot be neglected either. White magnolia likes well-drained, humus-rich, loose, slightly acidic sandy soil. Usually repot once every 2-3 years, preferably after Grain Rain, and add loose fertile soil. It is not cold-tolerant; except in South China, it must be moved indoors for winter care in other regions, and the minimum room temperature should be kept above 5°C. The best time to move it outdoors is from Qingming to Grain Rain.
4. Prune it in time. It sends out new shoots 3 times a year. Generally, the first time is in late February, the second time is in mid-June, and the third time is in early August. Because it grows and blooms at the same time after each sprouting, the flowering period lasts as long as 150 days. During the growing season, fertilize once every ten days, and apply phosphorus fertilizer 2-3 more times during the flowering period. At the same time, cut off diseased branches, dead branches, and leggy branches, and remove some old leaves to inhibit vegetative growth and promote more flowering.
5. Pest control must not be taken lightly either. Common diseases of white magnolia include chlorosis, anthracnose, and root rot; pests include scale insects, red spider mites, aphids, and slug moth caterpillars. The control methods for the main diseases are detailed below:
Anthracnose: It mainly occurs on leaves. In the early stage, it shows as chlorosis, with small yellow spots appearing, which gradually expand into round or oval shapes. Several lesions merge into irregular spots, with a light brown center and dark brown edges. When the lesion occurs at the leaf edge, it is semicircular, causing the leaf to become somewhat distorted. When the disease is severe, the entire leaf withers, turns black, and falls off. This disease is a fungal disease. The pathogen overwinters in diseased host tissues. Excessive watering in pots and too high humidity make it easy to develop. It generally begins in early June, and July to August is the peak period. Control methods are: improve the watering method, let water be poured in from the edge of the pot, and do not pour too much; combined with pruning, cut off diseased leaves and diseased shoot tips, remove and destroy fallen leaves to reduce sources of infection; during spring rain and plum rain seasons, spray an equal-amount 100-200 times Bordeaux mixture, 65% zineb 500-800 times solution, or 70% thiophanate-methyl 1000 times solution every ten to fifteen days, spraying 3-4 times in succession to suppress the occurrence of the disease.
Root rot: It is a fungal disease. Excessive watering or waterlogging of white magnolia can easily cause the root system to turn black and rot. In mild cases, growth is poor, and leaves wilt and fall off; in severe cases, the whole plant dies. Control methods: striving to improve soil drainage conditions is an important measure to prevent the disease. Water according to the principle of watering when dry and stopping when wet, water thoroughly when watering, and pay attention to loosening the soil; during continuous rainy days, prevent rain from falling on it and promptly pour out accumulated water in the pot; place more broken tiles and other drainage materials at the bottom of the pot. When placed outdoors, it is best to prop the flowerpot up with bricks to facilitate drainage; if the plant is infected during the growing period, chemical agents such as 65% zineb 250 times solution, 50% amobam 250 times solution, or 50% carbendazim 500 times solution can be used to drench the root soil.
Chlorosis: Also known as lack-of-green disease, it is a physiological disease. If the potting soil is alkaline and water with relatively high saline-alkali content is also used for irrigation, the leaves of white magnolia, which likes slightly acidic soil, will gradually change from green to yellow-white. In severe cases, parts of the leaves will necrose and turn brown. After the disease occurs, immediately spray a 0.5% ferrous sulfate solution on the leaf surface once a week, spraying 3-4 times in succession, and at the same time apply alum fertilizer water.
Pests and diseases: The main pests and diseases of white magnolia include chlorosis, anthracnose, red spider mites, scale insects, and so on. White magnolia likes acidic soil. If the soil is alkaline, or the irrigation water is also alkaline, it is easy to cause yellowing of white magnolia leaves and chlorosis with roots turning black and rotting. A 0.2% ferrous sulfate aqueous solution can be sprayed on the leaf surface once every 5-7 days, and a ferrous sulfate aqueous solution of about 0.5% can also be applied regularly to prevent and control it.
If you want your white magnolia to look more and more beautiful as it grows, you need to pay attention to its care methods.