Summer Pruning

Friday, August 18th, 2017 by Jenny Watts
    • Fall vegetables can be planted now for a fall harvest of broccoli, Brussels sprouts, cabbage, chard and lettuce.
    • Pansies and snapdragons can be planted now to replace long, leggy annuals. They will give you color this fall, winter and next spring.
    • Cut off the flower stalks of foxgloves, lupine, and delphinium after they bloom and you will get a second wave of flowers.
    • Feed rhododendrons, azaleas and camellias with a “bloom” fertilizer to encourage flowers for next spring.
    • Mums are the beauties of the fall garden. Choose plants now in a wide variety of colors.

Summer Fruit Tree Pruning

For many years pruning of fruit trees has been a winter activity. Pruning books tell us to prune when the trees are dormant, usually in January or February. But there is a new understanding of how trees respond to pruning that makes summer pruning the best way to control the size of your trees.

Winter pruning stimulates new growth because in spring the food stored by the tree over the winter bursts forth in a flush of growth. Pruned branches will burst out from many dormant buds. This works well with roses, for example, because the flowers are borne on new growth. So proper winter pruning will give you a healthy plant full of flowers.

In summer, food is made by the leaves through photosynthesis and this food is taken down into the roots and main branches and stored for next year’s growth. So summer pruning does not usually result in new growth.

There are two main kinds of pruning cuts used to prune fruit trees: heading cuts and thinning cuts. A heading cut is made to the middle of a branch, usually just above a leaf or bud, leaving a stub or short branch. Heading cuts are used to improve the shape of the plant by refocusing growth in a different direction. Winter pruning involves a lot of heading cuts to the tree.

A thinning cut removes an entire branch down to where it connects to another branch. So thinning cuts reduce the bulk of the tree and result in minimal regrowth. This is the kind of pruning best used for summer pruning.

Summer pruning can be spread out over July and August. It’s a little tricky because it’s harder to see the branch structure, but most summer pruning is done for size control. An apple tree cut all summer to a height of 7 feet tall will only grow, flower and fruit at that height or less. So next summer it can be maintained at that height without sacrificing any of the current crop.

Summer pruning can also be used for thinning the tree. Thinning cuts can be used to remove rampant growth and to let more light in through the canopy. More light to the interior branches will result in more fruit on the tree. Always leave enough foliage to protect the trunk and main scaffold branches from sunburn.

Watch your trees carefully and remove the “weedy” growth of suckers and watersprouts  as soon as they appear. Suckers are rampant growth that comes from below the graft and watersprouts are vigorous, upright branches that appear along the main branches of the tree. Both take energy away from the healthy growth of the tree.

It is recommended that apricot and cherry trees be pruned only in the summer. They are quite susceptible to disease when pruned during cool, rainy weather.

August is the last month to do summer pruning, so check your trees this week and make thinning cuts as needed to keep your trees under control.