Garden: Replenish plant soil with mulchPublished 7:14am Monday, June 9, 2014 Updated 9:15am Monday, June 9, 2014
As a gardener one is always making tough choices about the soil.
Should I just have some black dirt hauled in to spread on top of the native soil and call it good?
The thinking is that we have now provided a good spot for our perennials. While that may do for a year or so, it is not a permanent solution. To really do the job, and do it properly, the gardener must mulch.
Mulching reduces the weed population by shading the soil.
Most seeds need light to germinate. If thick enough, mulch prevents seeds falling on it to get to the soil to root. Seeds that germinate on top of the mulch are easily pulled out. Often, if left, they die because they can’t root properly.
As the mulch rots, it provides micro nutrients. This is especially true of any mulch that contains alfalfa.
Mulch also keeps the roots of the plants it surrounds cool and holds moisture. Especially important during the heat of the day and in dry periods.
Why go to all the trouble to spread leaves, straw, or in the case of trees, bark when you can just lay down fabric weed barriers?
This stuff was originally designed to place behind rock or block walls to prevent soil erosion and prevent weeds growing in said walls.
Yes it does hold weeds down for about 2 years. After that, annual weeds will land on it and take root.
Perennials will eventually push their way through it, tough as it is. Worse yet, it reduces oxygenation of the soil, prohibits spread of ground covers or plants you want to self seed. If it is laid under rock mulch, it will eventually get full of litter and dirt and have to be removed. It is a nightmare to plant through. And, it slows or even prevents moisture from getting through it.
Never, never use rock mulch around live plants. Even worse, is rock on top of the weed fabric.
The rock heats in the summer and fries the small feeder roots just under it.
If you must use rock, plant your plants in pots and set them on top of the mulch.
You will need to water them much more often as the hot rocks will heat up the soil in the pots, drying them out much more quickly than if they were on the deck or, better yet, on bare soil.
Putting rock on top of fabric makes everything worse.
The fabric lets dirt and debris stay on top of the soil. As a consequence, the rock needs to be cleaned periodically.
This entails removing the rock, hosing off the fabric and returning the rock to the area.
Organic mulch, composted compost, chopped leaves, pine straw, cocoa hulls, anything that once was alive, will eventually rot and improve the soil. It will make even clay soil, loose and fluffy.
After several years of mulching soil, the gardener will be able to plant peas by simply pushing them into the soil. And, as mulch also adds to the fertility of the soil, those peas will fly out of the ground and grow like Jack’s beanstalk. Plant and run.
Using damp newspapers under the mulch will not only help prevent weeds from popping though, but, when tilled in in the fall with the mulch, also helps lighten the soil.
After all, paper is a wood product. Just don’t use the colored section. That ink may or may not be soy based as is the black ink.
Bev Johnson is an Extension Master Gardener in Otter Tail County.