A lilac bush does best when it is trimmed every year.

Aug 21, If you want to prune your lilac to reshape it or to reduce its height, you could do it now, but it would be better to wait until spring. You see, if you prune in August, the lilac may produce new shoots that won’t have the time to harden off properly (prepare for winter) and they could be damaged by winter cold, obliging you to prune again in the stumpclearing.barted Reading Time: 2 mins. Apr 02, Most lilacs don’t require pruning until they reach about 6 to 8 feet ( m.) tall.

The best time for pruning lilac bushes is right after their flowering has ceased. This allows new shoots plenty of time to develop the next season of blooms. Pruning lilacs too late can kill young developing stumpclearing.barg: august.

Or, dig them out with a shovel.

Jul 08, Many of the newer lilac varieties grow quickly and might need pruning starting in their second or third year. In general, by the time a stem reaches more than 2 inches in diameter, it should be pruned. If you are diligent with annual pruning of your lilac, the shrub will grow to about 8 feet tall with flowers throughout the stumpclearing.barg: august.

Jul 14, Finally, there are a few of rules of thumb to follow when pruning lilacs: Trim mature lilac bushes so that they remain within 6 to 8 feet. Aim to have 10 to 12 main stems, each of them 1 to 2 inches thick.

Never prune more than one-third of the bush. Create a balance of older stems and new flowering stumpclearing.barted Reading Time: 2 mins. Home gardeners can choose between two different pruning methods. One way to renew a large, overgrown lilac is the removal of eucalyptus trees cut the entire plant back to within 6 to 8 inches of the ground in late winter (March or early April).

This severe pruning will induce a large number.

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Cut off all of the lilac bush's branches that are broken or show obvious signs of disease. They are more likely to cause problems than to produce a lot of flowers. Look for broken ends, damaged Missing: august.