The best time to prune is in the winter when there are no leaves and the plant is dormant. This way you can clearly see the shape and growth habits of the plant.
Old Wood and New Wood:
The branches with peeling bark and a pale white gray color are called “old wood” and branches that are a red, pinkish or orange in color are referred to as “new wood”.
We want to prune some “old wood” but not all of it. Blueberries produce fruit on last year’s growth, on the “old wood”. By carefully trimming the “old wood” we are encouraging the plant to focus its energy on creating bigger fruit on the “old wood”. It will also have energy to push out some new branches for future years and future growth. After a few years, blueberries will stop producing berries on the old wood, so we always want a mix of new wood and old wood to have a vigorous and productive plant.
When pruning, always have clean clippers that are sterilized with rubbing alcohol. Let them air dry and you are ready to prune. Also, when clipping diseased plants or branches, sterilize again before moving to a new plant so you do not transfer disease from one plant to another.
First thing is to remove any branches that are diseased, damaged or dead.
If you see branches that are a little whitish in color this may indicate, they are dead. Carefully scrape your fingernail along the bark of the branch and look at the color inside. We want to see a shade of green indicating it is alive. If it is a pale brown or sand color, it may be dead. You can scrape it in a few places to check. Go ahead and carefully remove dead branches accordingly. Remove branches that are broken. Any branches where the tips are a dark brown almost black in color and the branch is a much lighter color may indicate that branch is dying or diseased. Go ahead and remove that portion of the branch. Also, if you see tiny insignificant branches at the base of the plant, go ahead and remove those as well.
Another goal is to improve circulation and give the plant some openness in the center. When you see tiny branches in a cluster, you want to remove those so the plant can send energy to the larger branches. We also don’t want crisscrossing branches that will compete as they grow larger.
Remove any dead branch tips you see. If you see a branch is growing in the direction of another branch, imagine it with foliage and fruit. Will this branch impact the other one in the future? If yes, then clip it.
We do not want any shoots/branches intertwined. Imagine those branches when they are starting to grow new branches and are full of leaves and fruit, this will cause stress on the plant. Remove any such branch from the base at soil level.
Good rule of thumb when pruning, do not remove more than 30% of the plant.
Once pruning is done, you can add a little soil acidifier. In my experience adding less is better than adding too much with soil acidifier and you can follow this up with a 1-2 inch layer of high quality compost.
1. Clean and sterilize your pruning tool before starting
2. Differentiate between old wood and new wood
3. Scrape your nail against the bark of old wood to check if the branch is alive or dead. Check 2-3 spots.
4. Remove dead/diseased or damaged branches
5. Remove branches where tips are dark brown almost black and look like they are dying
6. Remove shrubby/insignificant growth at the base of the plant
7. Remove branches to open up the interior of the plant and remove crisscrossing branches
8. Remove branches growing towards the interior of the plant
9. Add soil acidifier carefully
10. Do not remove more than 30% of the plant
I hope you found this guide helpful. Hope you have a bountiful blueberry harvest this year!
Sophia Hasan @culinarygardensco