Copy of Fall Plant Pruning: Which Shrubs and Trees Should I Trim and When?

Before you start fall pruning, You need to ask yourself "When does this plant flower?" The flowering time frame is very important. Pruning at the incorrect time when prevent the plant from flourishing or even flowering at all. Here is a list of plants you should not prune in fall:

1) spring flowering shrubs an trees

2) ornamental grasses

3) marginally hardy perennials

4) roses

You might also consider leaving perennials that provide winter interest and provide seedheads to feed birds. These are not a necessity to the blooming in spring, but is something to consider. The top list is plants that shouldn't be for spring blooming.

So if I don't prune in fall, when do I prune?

Spring Flowering shrubs should be pruned as soon as they are finished blooming in spring. This allows ample time for the new flower buds to form for next spring. Examples of these are: One time blooming azaleas (spring only, not encore), forsythia, lilacs, quince, spirea. These are just some examples. There are more, just research our type of plant or watch the bloom time.

Summer- flowering shrubs should be pruned in late winter or early spring. The month will depend on your zone. Here in Arkansas, late February to early March is optimal timing. Examples of these type of plants are: crape myrtles, roses, most but not all hydrangeas, fruit trees, fruit bushes, and butterfly bushes. Once again, this is a small list.

Non-showy flowers should be pruned in late winter early spring too. Examples of these are cosmos, ferns, small wildflowers, and grasses.

Perennials that do not have decorative seed heads. These should be cut to the ground in fall. Examples are: Cora bells, astilbe, foxglove, Hosta, and dead nettle. Just like other plant types, these are only some examples but not all.

Tender plants should be pruned in fall. Lavender, rosemary are examples that should be pruned in fall before winter hits. So, how much time before winter? They should be pruned early fall, at least 6 weeks before a freeze. If you wait too late, they will not have time to recover before winter. Cut back about 1/3.

Perennials that are susceptible to disease should have leaves cut back in fall, as soon as they turn yellow. Examples of plants are lilacs, peonies, phlox and bee balm. There may be more plants, just do your research if you are unsure. Just google "examples of plants that are susceptible to disease that should be cut back in fall", or list your plant you are sure of and that search question. It's that easy to find the answer.

Hosta is another plant that should be cut back. They have been mentioned above in other categories. I need to do this now here in Arkansas. We have had a light frost, so they are beginning to turn yellow and browning. I will cut back everything to a few inches of the stem ticking up from the base of the plant.

I know this is a lot of information, and can be confusing. I know this is an important topic. We have lots of customer ask this question, and it's not always a black and white answer. Some varieties of azaleas and hydrangeas should be pruned at different times than other varieties. So, it is important to know your variety or at least when they bloom. If you pruned, and the following year they don't bloom, you possibly cut off the bloom tips at the wrong time of year, and now they aren't blooming at normal time. So, next year research or refer back to this article to make sure you are pruning at the correct time. Prune timing is important for the health of the plant and for proper blooming. You are always welcome to reach out to the Green Thumb Staff and we can help. Your local master gardeners, and extension offices can also help. Hope this helps and good luck with this upcoming year's pruning.