TREE/PLANT OF THE MONTH: Syringa vulgaris also known as a Lilac

This medium to large deciduous shrub is a sign of springtime, warm weather. Lilacs have a flush of lavender and sometimes white blooms in May. The species are quite fragrant but the many hybrids are not as odiferous. The hybrids usually will have larger more interesting blooms. They grow to be 10 - 15’ tall and can have a single trunk but most commonly have multiple trunks with suckers. They are often used as screens. Two common diseases are bacterial blight (Pseudomonas syringae) and powdery mildew. Plant in full sun with good air circulation to avoid these diseases. Lilacs are classic garden shrubs worthy of any garden.

Want tips on the proper pruning of your lilac bush? Check out the pruning guide on our Cyberlibrary (for members) and also available in Cass Turnbull's Guide to Pruning, 3rd Edition: What, When, Where, and How to Prune for a More Beautiful Garden. 

And check out our Lilac pruning YouTube video

 No Place for Old Trees

Read Cass Turnbull's thought-provoking series of articles collectively called No Place for Old Trees. Despite research quantifying the multiple values of the urban forest, trees and green spaces are in greater danger than ever before. Find out why and how developers captured the high moral ground in Seattle. And, learn how trees can and must go hand in hand with DENSITY. No Place for Old Trees is also available on the PlantAmnesty YouTube channel.

Cass' Density Rant

Part I
Part II: Infrastructure--Friend or Foe of the Urban Forest: Green Roofs and Bio Swales
Part III:  Infrastructure--Friend or Foe of the Urban Forest: Green Walls, Green Facades, and Permeable Pavement
Part IV:  Why We Don't Fund the Urban Forest and Green Space Programs
Part V:   Common Misconceptions

Cass Turnbull, founder and president of PlantAmnesty passed away on January 26th, 2017 while on vacation in Hawaii.  Please read about the Celebration of her Life and some of the many tributes to Cass on our memorial page.

On May 10th, Seattle Foundation helped Seattle non-profits raise more than $17 million.  Thanks to our donors, we reached our GiveBig fundraising goal. Your generosity will help us continue our work including:

Adopt-a-Plant Referral Service
Arbor Day Prune Renovation Workshops
Heritage Tree Program (with the City of Seattle) Spanish-speaking workshops and instructional videos
Master Pruner Classes Urban Forest Symposium (with UW Botanical Gardens)
Prune-a-Thon at Sky Nursery And lots, lots more!

 If you did not get a chance to give on May 10, we welcome your donation at any time! Contact us at or 206-783-9813.