The Aromatic Lilac | Washington State University

University:
Washington State University
Course:
BIOLOGY 401 | Plants and People
Academic year:

2021
Views:

170

Pages:

2
Author:

Lily Callahan

The Aromatic Lilac There is no flowering shrub more beautiful and aromatic than the lilac. Drive through any countryside and you will undoubtedly see long-lived lilacs growing next to farmhouses or by the roadside. Lilacs (genus Syringa) date back to the 1750s in the United States. George Washington and Thomas Jefferson planted them in their gardens and many of the first botanical gardens featured lilacs. If you ever get to Rochester, New York, take a good look around, because it is the Lilac Capital of the World! Highland Park in Rochester has 1200 lilacs of at least 500 different varieties. Just make sure you go during blooming season to get the full effect. White Lilac, variety unknown Lilacs are not particularly fussy plants and once established, they will thrive for many years with very little care. To get them off to a good start, plant your lilacs in well-drained soil and full sun. The more sun your lilac receives, the more flowers it will return to you. Lilacs prefer a soil pH of 7.0 to 7.5, which is much more alkaline than occurs naturally in the northwest. Therefore, an application of lime every fall will benefit the lilac. In early spring, apply a fertilizer high in phosphorus, such as 15-30-15. The best time to prune a lilac is immediately after flowering. Cut off the spent blossoms each year. More drastic renewal pruning will be necessary when the lilac gets leggy -- remove about one-third of the oldest stems at ground level each year for three years. This will encourage growth of new vigorous stems from the base. Remember that newer canes give the best growth and the most flowers. Lilacs are not susceptible to many diseases or pests, but there are a few. Bacterial blight is a fungal disease that starts out as brown spots on leaves and twigs and progresses to blackened and withered stems. Cut out infected stems as soon as possible, being careful not to spread the disease with your pruning shears. The best remedy is to purchase resistant varieties, but a copper sulfate fungicide can also be used to control bacterial blight. Powdery mildew is another common fungal problem with lilacs. This normally occurs in the fall and does not cause any damage to the plant. The potential for powdery mildew is Flower detail reduced if the lilac is planted in full sun and is pruned for good air circulation. Lilac leafminers can occasionally be a problem. The larvae of the adult moth cause large brown blotches and rolled leaves. Leafminers can only be controlled with a systemic insecticide. Oystershell scale resembles miniature oysters and can kill a lilac if the infestation is severe. Prune out infested branches. Frankly, choosing which lilac to plant is the most difficult part in growing them. There are at least 20 species and hundreds of varieties. Some grow very large, some stay small, some have variegated leaves, some have leaves that turn purple, yellow, or red in the fall, some have single flowers, some have double flowers, some flower early, some flower late, some are more fragrant than others, and then they come in many colors: lavender, pink, magenta, white, yellow, blue, purple with white edges, etc. etc. So do your research before you buy, or better yet, plan on putting in several! .