A Detailed Guide to the Planting and Cultivation Methods of the Four-Season Lilac (Syringa pubescens subsp. microphylla)

The Four-Season Lilac, also known as the small-leaved lilac (Syringa pubescens subsp. microphylla), has slender, delicate branches and a graceful tree form, with vivid flower colors, and it blooms twice a year. It is an excellent flowering shrub for gardens, suitable for planting in courtyards, residential areas, hospitals, schools, kindergartens or other gardens and scenic areas, and can be planted as a single specimen, in groups, or in mass plantings along roadsides, on lawns, at corners, and along forest edges, and can also be combined with other trees and shrubs, especially evergreen species.

The Four-Season Lilac is used in large quantities in the landscaping of northern cities such as Harbin and Shenyang. It loves light and is cold-hardy, has almost no pests or diseases, and has relatively strong drought resistance, giving excellent greening results in the Northeast region. The following introduces the cultivation methods of the Four-Season Lilac.

It is easy to cultivate and requires minimal management, and can be propagated by sowing, cuttings, grafting, layering and division. Sowing is carried out in spring and autumn. Before sowing, stratify the seeds in sand at 0-7 degrees Celsius for 1-2 months, and seedlings will emerge within half a month of sowing. For cuttings, take them 1 month after flowering, selecting robust, semi-lignified branches of the current year as cuttings. Grafting is carried out from late June to mid-July, using either bud grafting or stem grafting, with European lilac (Syringa vulgaris) or Chinese privet (Ligustrum quihoui) often used as rootstock.

1. The Four-Season Lilac prefers full sunlight and also tolerates partial shade. It has strong adaptability, tolerates cold, drought and poor soil, and has few pests and diseases. A well-drained, loose, neutral soil is ideal, and acidic soil should be avoided. It dislikes waterlogging and damp heat.

2. The Four-Season Lilac should be transplanted in early spring before the buds break. Apply sufficient base fertilizer in the planting hole first, cover the fertilizer with a layer of soil, then place the seedling and fill in soil. Water thoroughly once after planting, then water 2-3 more times and it will survive.

3. The Four-Season Lilac is highly adaptable and requires relatively minimal management. Normally, as long as you keep it free of weeds, prevent waterlogging during the rainy season, and water during droughts, it will grow smoothly. Lilacs do not like heavy fertilization, and excessive fertilizing must be avoided, as it can cause leggy branches and affect flowering. Generally, applying well-rotted compost once a year or every other year before winter is sufficient.

4. Before budding in mid-March, carry out shaping and pruning of the Four-Season Lilac, removing overly dense branches, thin and weak branches, and diseased or pest-infested branches, and cutting back vigorous-growing branches, so that the canopy is well ventilated and lets in light.

5. After the flowers fade, if you do not want to keep seeds, cut off the spent flowers together with the two buds at the lower part of the flower cluster, to reduce nutrient consumption and promote the sprouting of new branches and the formation of flower buds. After leaf fall, you can also do another round of pruning to keep the canopy round and attractive, which benefits growth and flowering the following year.

6. The Four-Season Lilac has very few pests and diseases. The main pests include aphids, bagworms and stinging caterpillars. They can be controlled by spraying with 800-1000 times diluted 40% dimethoate emulsion or 1000 times diluted 25% phosmet emulsion.