Garden Q.&A.
Cut Lilacs That Last  Q.  I would like to cut some lilac branches for display inside the house, but I haven't had good luck getting them to last more than a day or two. I always smash the stems, but it doesn't seem to help. How can I have long-lasting lilac bouquets?  A.  Long lasting and lilacs don't go together, no matter what you do, but here's how to have them look good for a week or so.
Start by getting up early -- lilacs cut before the day warms last longest. Select trusses that are about half open, and use a very sharp pruner to cut just above a leaf node. Since next year's flowers will form on this year's terminal branches, try to leave as many of those as possible.
Cutting the highest flowers first will encourage a nice full shrub with lots of bloom down where you can enjoy it. Use a ladder if necessary.
Once back on terra firma, remove lower leaves from the stems. Fill a vase with warm water, and add commercial flower preservative. Hold stems under warm water, and recut at a 45-degree angle.
If the stems are thick and woody, slit the bases a couple of times. The smashing we grew up learning to do -- I can see my mother, hammer in hand -- is no longer recommended; badly crushed cells can't take up water.
Display the lilacs in a cool place, out of direct sun and away from the fruit bowl (the ethylene gas given off by apples, bananas, tomatoes and other fruits hastens the decay of flowers). If you have room in the refrigerator, store the bouquet in it each night when you go to bed.
Don't forget to keep an eye on the water level -- lilacs drink a lot -- and to change the water every other day, so decay bacteria won't build up.
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