A Detailed Guide to the Latest Methods for Planting Lily Bulbs

Lily is also known as Qiangqu, fanjiu, shandan, daoxian, etc. It is a perennial herbaceous bulbous plant of the genus Lilium in the family Liliaceae, native to China, and mainly distributed in the temperate regions of the Northern Hemisphere such as eastern Asia, Europe and North America. Its flowers are elegant, its leaves are green and graceful, and its stems stand tall and slender. It is regarded as a precious new star among cut flowers. Now let us take a look at how to plant lily bulbs!

Growing Habits of Lilies

Lilies prefer cool and humid environments. Places with ample sunlight and slightly shaded environments are more suitable for lilies. They are averse to drought and extreme heat, and their cold tolerance is somewhat poor. The temperature for growth and flowering is 16-24°C. If the nighttime temperature in winter is below 5°C for 5-7 consecutive days, flower bud differentiation and flower bud development will be severely affected, delaying flowering or even causing blind flowers and split flowers. They prefer fertile, deep soil rich in humus, and most of all dislike hard clay. Slightly acidic soil with good drainage is best. Propagation methods include bulb division, scale cutting, seed propagation and tissue culture.

Planting Techniques for Lilies

1. Soil disinfection: Before planting lilies, the soil must be disinfected. The commonly used disinfection methods are steam disinfection and chemical disinfection. Steam disinfection is rarely used at present because it consumes a lot of energy and is troublesome to operate. Chemical disinfection uses 40% formalin diluted into a 1:50 or 1:100 solution and sprinkled over the soil at a rate of 2.5 kg/sq m. After sprinkling, cover with plastic film for 5-7 days, then uncover and let it air dry for 10-15 days before planting. Alternatively, 8-10 grams per sq m of carbendazim technical powder can be scattered into the soil for disinfection.

2. Thawing the bulbs: After the bulbs arrive, open the packaging immediately and place them in a 10-15°C environment to thaw. After they are completely thawed, disinfect them. Soak the bulbs in a 0.1% aqueous solution of captan, chlorothalonil, carbendazim, potassium permanganate, etc. for 30 minutes. You can also

3. Bulb storage: If the thawed bulbs cannot all be planted immediately, they must not be frozen again, otherwise there is a risk of frost damage. They can be stored at 0-2°C, but for no more than two weeks. They can also be stored at 2-5°C for up to one week, and the plastic film packaging must be opened.

4. Planting density: In spring and summer, the planting depth requires the top of the bulb to be 8-10 cm below the soil surface, and in winter 6-8 cm. Planting density varies depending on the variety, bulb size and seasonal factors. In spring and summer they can be planted more densely, while in winter, when sunlight is weaker, they should be planted more sparsely.

Planting Management for Lilies

1. Temperature management: To obtain high-quality lily cut flowers, temperature control in the greenhouse is very important. Within 3-4 weeks after planting, the soil temperature must be kept at a low 9-13°C to promote rooting. Too low a temperature will unnecessarily prolong the growth period, while a temperature above 15°C will lead to poor development of stem roots.

2. Humidity management: Before planting, the soil moisture should be such that it forms a ball when squeezed in the hand and breaks apart when dropped. In hotter seasons, if conditions permit, water once with cold water before planting to lower the soil temperature. After planting, water once again so that the soil and bulbs are fully in contact, creating good conditions for the development of stem roots. Subsequent watering should be based on keeping the soil moist, that is, a handful of soil should form a ball in the hand but not release water. Watering is generally done in the morning on sunny days. The relative humidity should preferably be 80-85%, and large fluctuations in relative humidity should be avoided, otherwise leaf scorch may occur.

3. Fertilizer management: In the early stage of growth, flowering lily bulbs mainly consume the nutrients stored in their own scales, so too much base fertilizer is not needed before planting. One month after planting, some fertilizer can be applied as a top dressing according to the soil fertility. Apply 10 kg per mu each time, once every 10-15 days, until 3 weeks before flower harvest. At the same time, attention should also be paid to supplementing trace elements such as iron, boron and zinc.

4. Light management: Light is an important condition for controlling quality, and lily flower bud development especially requires sufficient light. Insufficient light will cause poor plant growth and cause lily bud drop, paler leaf color and flower color, and a shorter vase life. When growing lilies in winter in northern China, due to the influence of glass or plastic film and other insulating materials, about 25-30% of sunlight is blocked. Therefore, in addition to keeping the surface of the glass and plastic film clean to ensure good light transmission, some varieties also need supplemental lighting, which can be provided with incandescent lamps.

5. Carbon dioxide: Carbon dioxide is beneficial to the growth and flowering of lilies. At 8-10 a.m. on sunny days, apply carbon dioxide gas pills in an unventilated greenhouse to increase the carbon dioxide content inside, or use other methods.

Disease Control for Lilies

1. Blue mold

[Symptoms] During storage, white spots grow on the rotting spots of the scales, and then fluffy greenish-blue patches develop. After infection, even at a low temperature of -2°C, the rot will gradually increase. The pathogen will eventually invade the basal plate of the bulb, making the bulb worthless or causing the plant to grow slowly. Although infected bulbs may look unhealthy, as long as the basal plate of the bulb is intact, the growth of the plant during planting will not be affected. After planting, the infection will not transfer to the stem, nor will it infect the plant from the soil.

[Control] Store the bulbs at the recommended minimum temperature. Do not plant bulbs whose basal plates have already been damaged. Before planting, diseased bulbs must be soaked for 30 minutes in a 0.1% aqueous solution of fungicides such as captan, chlorothalonil or carbendazim, and then planted. After planting, maintain an appropriate soil temperature.

2. Rhizoctonia

[Symptoms] If the infection is mild, it only harms the leaves in the soil and the green leaves at the lower part of young shoots, with sunken light brown spots appearing on the leaves. Generally speaking, although the growth of the plant is somewhat affected, it can still continue to grow. In severely infected plants, the growth of the upper part is hindered, and the white leaves underground as well as the lowest leaves above ground will rot or wilt and fall off, leaving only brown scars on the stem.

[Control] Disinfect soil that is suspected of being infected with a soil disinfectant, and after disinfection it must be ensured that the soil is no longer infected. If the previous crop has already shown infection, ordinary soil disinfectants cannot be used. In that case, before planting, pre-treat the soil with an agent for controlling Rhizoctonia (fully incorporated into the soil to a depth of 10 cm).

3. Phytophthora

[Symptoms] Foot rot of the plant (Phytophthora) will hinder growth or cause sudden wilting. Soft rot occurs at the infected area at the base of the stem, turning dark green to dark brown and spreading upward. The leaves turn yellow, and discoloration begins at the base of the stem. Similar soft rot infections often also occur on the above-ground stem, causing the stem to collapse or bend.

[Control] Disinfect infected soil with a general soil disinfectant. During cultivation, fungicides that control Pythium can also effectively control foot rot. Ensure the soil has good drainage conditions and prevent the crop from remaining wet for a long time after watering. In summer, the soil temperature should be as low as possible.

4. Pythium

[Symptoms] This type of fungus attacks both individual plants and plants within an area. Plants become stunted, lower leaves turn yellow, upper leaves become narrower, leaf color is paler, and they often wilt. In plants affected by root rot, flower buds shrivel. When the plant is pulled up, transparent, light brown rotting spots can be seen on the bulb and root crown, or they have completely softened and rotted.

[Control] Disinfect infected or suspected infected soil with a general soil disinfectant, keep the soil temperature low in the early stage of cultivation, and adopt correct cultivation procedures throughout the cultivation period. Cultivation in boxes containing potting soil and peat can keep Pythium under control. After the crop has emerged or in cases where Pythium infection may already have occurred, fungicides for controlling Pythium that are easy to spray onto the crop can be used, preferably in the evening. Spraying water for a few minutes (about three minutes) before applying the fungicide will significantly enhance the effect of the fungicide, and the crop can also be rinsed clean.