Mulching for Success

Phillip Peters
Adams County Master Gardener

With the best part of the gardening season ahead of us, let’s take a look at how we can make the garden more successful while cutting down on weeding, one of gardening’s more onerous chores.

Getting the plants in the ground and the seedlings up is just the start of our enjoyment of the garden. Bringing the plants to maturity and reducing the competition for water and nutrients from unnecessary weeds is an on-going effort. Proper mulching can go a long way to make our garden more productive and weed free. Be it the vegetable garden or the flower bed, there are products that will make you happier with the garden without requiring a big outlay of money or effort. An early start is the key here.

There are essentially three reasons to apply mulch in spring and summer. First, it can help warm the soil earlier and ward off frost on unexpected chilly nights. As the season progresses and the weather gets drier and summer heat more intense, a covering of mulch will help retain moisture near the roots of the plants and retard evaporation. Lastly, this same cover will retard and cut down excessive weed growth, reducing the number of weeds in the garden and making those that do start easier to pull.

You may have already begun your gardening by using row covers. These are light-weight filmy materials to put over young plants early in the season to prevent damage from frost or to keep the day’s warmth from escaping on chilly nights. As the season progresses, they can be used to prevent moths and borers from laying their eggs and keep beetles from damaging leaves. These are mostly used in the vegetable garden.

There are several types available, ranging from plastic stretched over hoops to light fabrics whose use is essentially protection from insect damage. The plastic retains heat better and is most useful early, at the end of spring, to gain a couple extra weeks’ growing time. The fabrics can be used at that time for heat retention or later to protect plants when insect pests are active on a particular crop. You want to keep the borers and leaf eaters from attacking your plants; however, you don’t want to prevent the beneficial insects from pollinating them. This involves careful attention to timing. Keep a close eye on your garden to see when pests are beginning to become active. Many garden guides or the local Cooperative Extension office can help you know when to apply them.

Before leaving the vegetable garden, we should also mention using straw or grass clippings as a mulch along the rows. Due to their appearances, these are not frequently seen in the more formal flower garden. A 2" to 4" cover will allow moisture to get to the roots and retard its evaporation during the day. This will cut down on how frequently you need to water, thereby saving you money and time. Some weeds will grow in the straw, but their roots will be shallow, making them easier to remove.

Be sure to use a good quality straw. Do not use hay or clippings that have gone to seed. The weed seeds will germinate and you will have the very problem you are trying to eliminate.

You may have also seen various plastic or synthetic landscape fabrics in the garden store. They are available in several thicknesses and a variety of colors. These can be very effective if applied properly and covered with 2" to 4" of a natural mulch – it takes away the artificial look. Landscape fabrics are a very heavy weave of plastic material. They are guaranteed for 5 to 15 years. Most fabrics are permeable to water. Cover them with a natural mulch. Be aware that not only will you have to renew the mulch from time to time, but you should remove any weeds that get started in the mulch. If they ever put down roots through the fabric, they will be virtually impossible to remove.

The same applies to plastic covers. Both landscape fabric and the plastic come in rolls. The material should be cut to fit your bed and held down by garden staples at the edges. Bury the edges under several inches of soil to keep the material in place and to give the garden a finished appearance. Leave a generous cut-out around the crown of your plants and shrubs so they can breathe and water can get to them. Remember plastic is impermeable to water. It will maintain the moisture beneath it, but there has to be some space around the plant to let the water in. If you are using the plastic to change soil temperature or to influence plant growth, do not cover it with natural mulch, and make sure the plastic is in close contact with the soil.

Plastics come in several colors. There is research to show that red plastics can increase tomato yields; blue helps potatoes; orange, turnips. You may also see white or silver plastic. These colors seem to keep down aphids and other insects. Avoid yellow at all costs; it attracts a wide variety of insects, especially cucumber beetles. There is a reason Japanese beetle traps are yellow! Regardless of color, plastic will degrade over time and will have to be replaced every growing season if it is to be effective.

For a more successful and labor-free summer garden, don’t forget to put down mulch.

Read other articles on gardening techniques

Read other articles by Phillip Peters