Gardens Galore: Black Knot Of Cherry ~ By Karen Brewka

Check out Karen's tips to care for this pretty tree and it will present a beautiful display come spring.
If you have a question about your garden you can ask Karen by emailing the Gateway Gazette ~ gazette@telus.net.



While pruning my flowering crab, I was thinking about what to write for the first column of 2012.
Well, pruning is a good topic. It's so easy to get some pruning done this winter without piles of snow everywhere. I'm doing some “heading back” on my crab. The branches hang over my deck and it's beautiful when blooming. But, the grosbeaks leave such a mess with dropping fruit and other 'items' that I decided to reduce the overhang. Heading back means taking a branch off at a lateral bud, twig or branch. Two important things: don't leave a stub and don't take off a large branch while leaving on a tiny twig. The twig left on should be at least 1/3 the diameter of the branch you took off.
While heading back a branch, I noticed there were really no good laterals and it looked bad. So, I'm going to “thin out” that branch. “Thinning out” means taking the branch off at the trunk. In the case of a shrub, it means taking the stem out at the base of the plant. Things to remember: don't leave a stub and don't take the branch off flush with the trunk. The slightly raised bark around the branch, where it is attached to the trunk, is called the 'collar' and needs to stay on the trunk. At the top of the branch attachment, the collar is the raised wrinkly bit of bark and at the bottom, it is the raised humpy bit. The cut will be angled toward the trunk. A perfect cut will result in a doughnut- shaped ring of wound wood around the cut location. Then you will know if your cut was too close or too far from the trunk.
Black Knot of Cherry is a fungal disease brought to us from infected nursery stock and planted in our yards and boulevards. Hard black lumps appear on branches of trees of the cherry family. Prune off these lumps by heading back or thinning. The infection extends into the branch so take off at least 8 to 10 inches below the lump. Bag the lumps and when it's safe to burn them, do so. This disease will eventually kill the branch it appears on and will kill the tree if it gets into the trunk. Black Knot has spread to infect wild Saskatoons in the river valley.
Take a look at your Schubert Chokecherries and Mayday trees. If you've got Black Knot, prune it off!
For more information about pruning (and pictures), check out ISA Pruning and for Black Knot, check out Alberta Agriculture Black Knot on the internet.
The Valley Neighbours Garden Club meets on the second Thursday of each month at Valley Neighbours on Sunset Boulevard in Turner Valley. The club welcomes new members. For information call Bea at 403–933–7131. The Horticultural Club meets every second Tuesday of the month at 7:30 pm. For information call Sheila at 403–931–3989.