Saturday, February 3, 2018

Gardeners' Holidays 2018: Pruning Day

Winter seems to be at its peak right now. When I ventured outside yesterday for my afternoon walk, it was so cold that I turned back before I'd gone two blocks. Today's not as bitter cold, but it's still below freezing, and our yard is a flat, barren wilderness, with nothing to be seen but dead grass and bare branches. And according to old Punxsutawney Phil, we've got at least six more weeks of this to look forward to.

Yet if winter is truly at its peak, that means its decline must be just around the corner. And indeed, if you look closely, it is possible to detect the first faint sigs of approaching spring: tiny hints of leaf buds on the branches of our plum trees. So as little as it feels like spring right now, it's none too early to start planning if we want our garden to be ready when it arrives.

Our seed order from Fedco has arrived (with the exception of two plants that were on back order), and we've already gone through it and determined just how much we want to plant of what. The first batch of seedlings, the parsley, is due to be started soon, and Brian has already dug out a bunch of dirt to sterilize for our seed-starting system (even though he had to chip it out with the vicious Structron Super Shovel, because the ground was frozen solid). But in addition to these usual February tasks, we had one more job to attend to this year in preparation for the coming growing season: pruning our plum trees.

For the last two years, our plum crop has been suffering greatly from brown rot. I initially tried to deal with it by simply removing any diseased fruits as soon as I spotted them, but when the depredations of the disease were combined last year with pilfering by squirrels to deprive us of almost our entire crop, I decided I couldn't afford to mess around. So I did some research to try and figure out how to manage both these pests effectively—first, to keep the fungus at bay long enough to let the fruits ripen, and then to keep the squirrels' grubby little paws off them until we were able to harvest them.

The sources I consulted said the best way to prevent brown rot is to prune the trees effectively. Beyond just removing all fruits and branches that show any sign of disease, you need to prune the entire tree to keep the branches from coming into contact with each other. Good air circulation around the fruit is key to keeping it healthy. And the best time to do this pruning, they said, is in February, right before the trees start to leaf out in earnest.

Since Brian is a foot taller than I am and has better grip strength, he did the actual pruning, while I stood back from the trees, directed him toward the best spots to clip, and gathered the branches into a pile after he'd removed them. The guidelines he was trying to follow, based on some reading he'd done online, were:
  1. Wherever possible, remove branches that directly overlap with other branches.
  2. Also, remove branches that point inward toward the main trunk of the tree.
  3. When removing a branch, clip it as close to the trunk or limb as possible without damaging the "collar" (a ring of dense wood immediately surrounding the base of the branch).
  4. Do not remove more than one-quarter of the "crown" (the total volume of branches).
He quickly found that it wasn't possible to stick to these rules exactly, since removing every branch that overlapped another branch would definitely have meant taking off more than a quarter of the total. (Probably that's partly our fault, since we neglected to prune these trees for the first few years we had them. It may be easier next year.) However, he was able to cut away all the worst offenders without stripping the trees down too heavily. Here's a before-and-after comparison of the Mount Royal tree, which has the widest branch spread of the three; the difference is subtle, but you can tell there's a bit more light coming through the branches in the second picture, and the pile of trimmings on the ground is testimony to how much we took off.

This is just the first stage in our three-point plum protection plan. Some time before the trees actually blossom, we plan to pick up a bottle of an appropriate fungicide that's not too hazardous and spray the trees with it throughout the spring. Planet Natural recommends a copper or sulfur-based fungicide, applied weekly, starting as soon as the blossoms first start to open. I'm hoping that if we aggressively strike back against the fungus this year, the trees will have a clean bill of health next year, and regular pruning will be sufficient to keep them disease-free after that.

Then, once the fruits start to ripen, we plan to use every trick in the book to deter squirrels. We'll apply Tree Tanglefoot to the trunks, covering every branch within jumping distance of the ground, to discourage the little buggers from climbing, as well as scattering our own hair around the base of the trees to deter them from approaching. If need be, we'll even offer them something tastier to eat—maybe birdseed, which we know they like—some distance away from the trees, in the hopes they'll go for that and leave the fruit alone.

Here's hoping these efforts will allow us to enjoy a decent crop of plums this summer. In the meantime, we'll just stay nice and snug inside with our crop of little seedlings until it's finally warm enough to get them into the ground.

No comments: