Calla lilies are a common wedding flower yet are often in short supply, and the reason is that cultivation techniques are inadequate.

Calla lilies are a common wedding flower yet are often in short supply. The reason is that cultivation techniques are inadequate.

Cultivation techniques

Potting

Soil mixing: the potting soil should be fertile, neutral or slightly acidic. You can use 2 parts finely crushed pond mud (or clayey fine sandy soil), 1 part leaf mold (or compost), add an appropriate amount of superphosphate and decomposed human and livestock manure, and mix them together.

Propagation is usually carried out after flowering: the small corms around the tuber are peeled off and grown for one year, and they bloom the following year. Through experiments, the author found that using the root-sucker division method allows them to bloom in the same year.

The specific method is: from late June to early August, while repotting, break apart well-developed large divisions with roots by hand (preferably without a knife) and plant them in prepared pots. If used for cut flowers, plant 2 to 3 more divisions, and place them in a cool place after planting. Propagated this way, they can bloom in September to October of the same year.

Management

Light and temperature: calla lilies like a warm, humid environment with slight shade, but during the flowering period they need ample sunlight, otherwise the spathe will be tinged with green, affecting quality. You must ensure 3 to 5 hours of light per day, otherwise the leaf stalks will elongate and reduce their ornamental value. Calla lilies are not very cold-hardy, and must be moved into a greenhouse in mid-October. In summer, under shaded conditions, water should be sprayed frequently to cool down and maintain humidity.

Watering and fertilizing: calla lilies like moist, fertile soil, which is what is often called "heavy fertilizer and heavy water", so water more during the growing period. For topdressing, liquid fertilizers such as decomposed soybean cake water can be applied alternately with chemical fertilizers (compound fertilizer or diammonium phosphate), with topdressing every 2 weeks. When applying liquid fertilizer, never let the fertilizer water pour into the leaf sheaths, to avoid rot. Someone previously said: "Stop fertilizing when flower buds appear." After experimental comparison, the author believes that after buds appear, the amount of fertilizer should be increased, thereby ensuring a long flowering period, large and vivid flowers, and continuous buds, blooming all year round.

Use of ferrous sulfate: in potted calla lilies, topdressing with ferrous sulfate is an important part of the experiment. Topdressing with ferrous sulfate can make calla lily leaves larger, thicker and greener, smooth and glossy, and the leaf stalks less likely to elongate, thereby keeping the leaves attractive. At the same time, it promotes flower bud formation and prolongs the flowering period. The specific method is: dilute ferrous sulfate into a 2% solution, apply it once every month, and water thoroughly each time.

Propagation methods

Propagation is mainly by division of corms. After the plant enters dormancy, peel off the small corms around the tuber and plant them separately. It can also be propagated by sowing; after the seeds mature, sow them in pots immediately. The suitable germination temperature is about 20°C.

Division: when the old leaves gradually wither after flowering in May to June and new leaves grow, or when repotting in mid-September, peel off the small tubers around the mother plant and pot them up by grade. They generally bloom 3 months after planting.

Taboos

Avoid low temperature and dryness. Calla lilies like warmth and humidity and are not cold-tolerant. In winter, the indoor temperature generally must not be lower than 10°C, otherwise flowering will be affected. During the growth and flowering period, take care to keep the potting soil moist, and frequently spray and wash the leaf surfaces with warm water to keep them fresh and green.

Avoid smoke and dust pollution. Calla lilies require fresh air for growth and flowering, and are rather sensitive to smoke. Stove coal smoke and cooking fumes will both cause poor growth of calla lilies, leading to yellow leaves and dropped flowers.

Avoid insufficient light. Calla lilies like light during both the growing period and the flowering period; especially around the Spring Festival flowering season, if light is insufficient, the flower buds that emerge will fail to open and drop.

Avoid poor ventilation. In winter, poor indoor ventilation often leads to scale insect damage, accompanied by sooty mold. When there are not many scale insects, they can be brushed off with a soft brush. For sooty mold, wipe off the black soot powder with clean water; in severe cases, spray with 1500 times diluted thiophanate-methyl or carbendazim for control.

Pest and disease control

During the dormant period or storage, tubers are prone to rot. The tuber surface can be sprayed with a 1000 times diluted solution of antibacterial agent 401 acetic acid, then dried and stored. Pests include red spider mites and thrips, which can be controlled by spraying with 1000 times diluted 50% chlorobenzilate and 4000 times diluted 2.5% deltamethrin emulsifiable concentrate respectively.