When to Sow Lupines? Master the Best Planting Time
Lupine (Lupinus) belongs to the legume family, and its stems grow upright. Many small branches grow from the base, and the whole plant is covered with brown stiff hairs. So, when should lupines be sown?
1. When to sow lupines
Lupine seeds can be sown in spring or autumn. The spring sowing time is from February to April, and the autumn sowing time is from September to October. However, autumn sowing is most suitable. After autumn sowing, they will bloom from April to June of the following year. Plug trays are mostly used for sowing, with one seed per cell, and a loose, uniform, water-retentive and breathable soil is used for raising the seedlings.
2. Daily management of lupine cultivation
1. Temperature
Lupines like a cool climate and cannot tolerate heat. In winter, they can briefly tolerate low temperatures around zero degrees. Generally, gardeners are advised to move them indoors when the temperature drops below ten degrees. Lupines also cannot tolerate high temperatures. When the temperature is above 30 degrees, they will go dormant. Many gardeners choose autumn sowing, enjoying flowers in spring and seeds in early summer, to avoid the high-temperature period in summer. Gardeners who sow in spring should pay attention to summer care, because lupines are very prone to diseases when overwintering through summer.
2. Light
Lupines like light. Under sufficient light, they grow well, with sturdy branches, thick and long flower spikes, and many bright flowers. They are slightly shade-tolerant. Under insufficient light, they tend to grow leggy, with weak branches, dull leaf color, small flower spikes with few flowers, and a low seed-setting rate, which greatly affects their ornamental value.
3. Soil
Lupines have certain soil requirements. They are suitable for growing in slightly acidic soil. Gardeners in the north should pay attention to one point: avoid using ferrous sulfate and aluminum sulfate for a long time to adjust the acidity and alkalinity of the soil, because the cations in these two types of regulators will accumulate in the soil and poison the flowers. It is recommended to use pond mud mixed with leaf mold as the potting soil for growing lupines.
4. Fertilization
Lupines do not have high nitrogen fertilizer requirements, because the rhizobia parasitic on their roots can fix nitrogen and provide nitrogen fertilizer for plant growth. However, they have relatively high requirements for phosphorus and potassium fertilizers. Sufficient phosphorus and potassium fertilizers can promote flower bud differentiation, increase the length of flower spikes while making the flower color vivid, and can increase the seed-setting rate after flowering.
5. Propagation
Lupine propagation is mainly by seed sowing. Generally, gardeners choose autumn sowing. During winter care, they can enjoy the leaves, in spring they enjoy the flowers, and after setting seeds in summer the plants die. This exactly avoids the situation where the high-temperature period in summer, when diseases are frequent, is difficult to manage. Some gardeners also cut branches sprouting from the roots in spring for cuttings. These branches are cut into 10 cm sections, soaked in rooting powder, and then inserted into clean wet sand. Generally, in about a month and a half, a complete root system can develop and they can be transplanted.
6. Pests and diseases
Common lupine diseases include root rot, rust, and powdery mildew. These diseases are all caused by fungi. The causes of disease are related to high temperature and high humidity, and excessive planting density leading to poor air circulation. Improving environmental air circulation can effectively prevent the disease. Some flower nurseries spray pesticides regularly to prevent disease. Over time, the pathogens will develop resistance, making it more difficult for gardeners to deal with the disease when they find it after buying mature flowers. Therefore, when purchasing, pay attention to observation. It is best not to buy those with white pesticide residue on the leaves.