When is the best time to trime a crape myrtle bush? Mine is too big.

http://www.southernliving.com/garden/grumpy-gardener/what-concerns-p

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http://www.southernliving.com/garden/grumpy-gardener/what-concerns-p

At the end of the summer when it cools down and the blooming season is over (sometimes they can bloom twice). They should bloom like crazy next year.

Here are a couple links for you. I prefer the informal pruning method and where I live we trim or prune in late winter or early spring and blooms all summer long. Good luck!

https://www.gardeningknowhow.com/ornamental/trees/crepe-myrtle/pruning-crepe-myrtle-trees.htm

https://www.gardeningknowhow.com/ornamental/trees/crepe-myrtle/best-crepe-myrtle-pruning-time-when-to-prune-crepe-myrtle.htm

Major pruning time is definitely during your cool season. Don't forget that crepe myrtles can be cleaned up from the bottom at any time. I trim off all my lower trunk suckers when they show up. Of course if you have a huge tree variety that it making a mess (I do), you can trim some of that off at any time without harming the tree.

if you trim off the blooms when finished plus a little growth here in Texas they will keep blooming til it's colder which can be a long while. Some Super Blooming liquid fertilizer (the middle no.) will review them even more.