Compost is best thing you can do for garden
For openers, I’d like to thank everyone who turned out for the compost class Feb. 24. The room was filled to overflowing!
I think everyone, including myself, came away with some new information. I was disappointed that not many of you said “hello.” My wife, Ann, tells me that’s because I have a perpetual scowl, but, really, I’m always ready to talk about plants.
Something came up at the class that needs clarification. Someone from New Mexico State University said something that somehow got misinterpreted as meaning that compost is 50 percent phosphorous!! WHAAAT?? How can something as exquisitely organic as compost be composed of half an inorganic element?
In concentrations of this sort phosphorous is extremely toxic. No worms or any other critters could possibly live in this environment. Phosphorous helps some plants flower and fruit when used as part of a fertilizer, but compost is an amendment to be mixed liberally with the soil. I look at compost as sort of horticultural ketchup — everything’s better with a liberal amount of compost. It’s like location is to real estate — the three most important things for a good garden are compost, compost and more compost!
Because of its heat, a compost pile works great for rooting cuttings or starting seeds, or even keeping potted plants warm over the winter. I’ve been amazed at the things I’ve been able to root just by sticking them in my compost pile. With 50 percent phosphorous, it’d never happen. So don’t hesitate to use plenty of compost. It’s really essential in our sandy, alkaline soils.
Another question came up about composting pine needles. They make terrific, slightly acidic compost. At my nursery where we had thousands of pine trees, we planted rhododendrons and azaleas in a mix of old, black pine needles, and, boy, did they grow!
I’ve gotten a lot of emails from people who have had desert willows (Chilopsis linearis) and other trees split. This usually occurs because the trees have narrow branch angles that trap bark and water, which sets up rot, which weakens the union, eventually causing it to split. You can spot this problem by looking for a seam extending downward from the crotch. If you see this, remove the branch even if it means having the tree look lopsided for awhile, or at least, shorten the branch to take the weight off it.
Desert willow and many other fast-growing trees are especially prone to splitting. One way to control this is by pollarding.
This involves selecting several strong branches to serve as the framework of the tree and removing everything else. The selected branches are then cut back to more or less uniform lengths and allowed to sucker out. Every winter the new growth is removed back to the original cut. Eventually the branch ends become thick and clublike, making for a very striking winter profile.
When the tree leafs out the profuse sucker growth makes it very full. This only works on deciduous trees and ones that bloom on new growth — like desert willows.
I’m starting to see trees and shrubs showing up in big warehouse-type stores. The problem with this at this time of year is that in a heated building, the plants break dormancy and start growing. When you take them outside and we have a March freeze — and we always do — all that new growth dies off. The plant may not have enough stored energy to leaf out again, in which case it dies. If it does releaf, it will be badly weakened and do poorly for several years.
So don’t jump the gun! Wait until late April or early May!
NEXT: How to pick out a tree.