The subject of mulch is obligatory, I guess, for any garden writer, and I have on a number of occasions fulfilled my obligation in that regard, so, here in the post-dog days it is time again to reconsider the subject.
Dog days elapse on Aug. 11 each year. It is not the time all the dogs sleep under the porch, but instead has to do with astrology and the rising of the dog star Sirius in the night sky.
Whatever. Gardeners, and a lot of other people, value the date because it supposedly leads to cooler temperatures both day and night.
In our climate it is most often a pipe dream, but “hope springs eternal in the human breast.”
Be all that as it may, mid-August is an apropos time to talk about mulch, because fall planting of woody plants, and some herbaceous perennials as well, need a good mulching to stand up to heat and drought of the season.
One of the most valuable facets of mulch is to hold moisture in the ground. Newly set plants of every kind need all the succoring they can get so root establishment can be generated outside the diameter of the potted plant in which manner they have been received.
Unmulched, a newly set plant can easily dry out in a day or so this time of year.
Once you have set your plant, properly I hope in improved soil, the idea is to apply a mulch out from the stems a little farther than the diameter of the root ball.
Be sure to leave a “donut” of open soil just around the stem of the plant. This could be a few inches for a small perennial up to a foot or so with a large shrub or tree.
OK, so we have the new plant properly mulched.
Even then, conscientious watering is a must for the first month or so, at least until fall rains, if there are any, take over the chore at nature’s hand.
Now, then, what about established plants? Mulching is not as critical in that case, but it never hurts when done properly, that is to say, not mounding up a volcano of mulch right around the main stem.
How often do we see a huge pile of mulch around even established trees to the point the lower trunk is buried in a sodden mass of shredded bark?
It is totally unnecessary and not only does no good but does much evil.
The moisture trapped against the hapless bottom of the tree trunk can easily rot, inviting entry by various pests, including wood-eating black ants and even termites. So, don’t mulch around trees once they have been in situ for a few years.
Another mistake that is made is using the wrong kind of mulch. Said shredded bark is virtually de rigueur in many minds and the term mulch is often heard as a synonym for shredded bark, a la Kleenex for face tissue and, back in the day, Kodak for camera.
Trees and shrubs are quite suited to bark mulch usage, but more tender and persnickety plants can succumb to rot or other mishap when heavy bark is piled on. In such a case, pine needles, cocoa hulls or small gravel is a better choice. Then, oxygen is given free passage to the plant and smothering is not as prevalent.
I am often asked what I use for mulch. Other than for occasional application to newly set plants, my stock answer is “more plants.”
In a mixed bed or border, tight planting in improved soil actually needs nothing more than the protection of good neighbors.
JIMMY WILLIAMS is the garden writer for The Post-Intelligencer, where he can be contacted on Monday mornings at 642-1162.