trunk

I've got about a 50 year old lilac clump/stump in a 12x18" pot and it's really starting to look good. It was dug from my parents yard about 4 years ago, as they wanted the space for something else, and I just couldn't let them kill the lilac. It has set a few flowers since being potted, but pruning for branch development has kept flowers to a minimum. Perhaps someday it will get to a point where I don't mind letting a few branches flower each year, just to have the color around. As has been said though, the leaves only seem to miniaturize to about half size so far, so it will need to be a large bonsai to really look good.

In my experience the best trees for collecting are those in the high elevations, with contorted trunks and branches from the heavy snow loads when young. Still, there could be local enthusiasts interested in your trees. You could try posting in the FREE section of Craigslist but could get a lot of nuts calling. I would suggest looking for local clubs and contacting them. https://www.google.com/search?q=massachusetts+bonsai+clubs&ie=utf-8&oe=utf-8

Where they naturally occur, or in the landscape, Syringa demands good drainage and doesn't tolerate wet feet well. Your soil is very water retentive, and this is a significant problem because it makes it very difficult to water w/o over-watering in the shallow pots we use. Your focus should be on maintaining its viability until it can be repotted in spring. Too, I'm not sure your plant will experience enough chilling in SF, even outdoors, to satisfy its dormancy needs. Are there lilac trees in the landscape where you live? Your tree wants to be outdoors, permanently. You should monitor it's moisture needs with a piece of 1/4" wood dowel rod that's been sharpened in a pencil sharpener, or a bamboo skewer - only water when it actually needs watering, and you should water to well beyond the saturation point, so at least 15-20% of the water used to wet the soil exits the drain hole. After you water, hold the pot over the sink and move it up and down. You'll discover that on the reversal from downward to upward, excess water will exit the pot. This is very important. Hopefully, this strategy will help you keep the plant viable until spring, when you can repot into an appropriate soil. It needs regular fertilizing as well. Typically, Syringa wants a low N fertilizer in order to bloom. Your focus shouldn't be on blooming at this point - it should be on getting the tree healthy and development. For now, Foliage-Pro 9-3-6 would be an excellent fertilizer, and can be used on virtually all the plants you grow. I use it for more than 75 species of bonsai, and all my 'other' plants. I only do a little tweaking for a few plants - tomato, hibiscus, boxwood. Let me muse, please: No one is a 'natural' when it comes to bonsai. Some, unlike me, are blessed with exceptional artistic vision; and some, as a byproduct of their profession, already have a sound understanding of plant physiology - how plants work. The rest of us, if we're to become proficient to the point that we can consistently keep our trees healthy, will have to either invest the time it takes to form a good understanding of soil science and plant physiology, or, be content to continue buying plants to replace those that are no longer viable. The later gets to be frustrating very quickly, and is the reason more than 95% of those who try their hand at bonsai don't pursue it beyond a year or two. Wishing you the very best luck. If there are questions you think I might be able to answer, don't hesitate to ask. Your battle, re your tree, is against poor root health. Al