The saying, “give weeds an inch and they’ll take a yard,” is certainly true in our intense growing season. Weeds are probably the number one reason gardeners give up on gardening. After a heavy rain like many had last week, the weeds seem to come up everywhere.
First, where do all those weeds come from? Many weed seeds come in with a load of soil, manure or compost that has not gotten hot enough. Birds are also very efficient at planting anything that goes through them on a trip over your garden. Add to that all the mice and chipmunks that like to plant things, the wind that blows in seeds, the lawnmower, our big feet – well, you get the picture.
Weed seeds are viable much longer than most garden seeds. Kochia, pigweed, and purslane can remain viable up to 50 years, just waiting to be brought close to the surface and light when you till or hoe. Long viability means weeds will always have the advantage in a garden or flower bed.
As you can see, we are not going to get rid of the source. One approach to take is to beat them with good garden practices. If you till your garden, try to do it in the early spring. This is better for the health of all the microorganisms in the soil; it brings up the weed seeds so they can germinate before you plant your vegetables. When you see that first flush of weeds, do a shallow hoe in two directions. That will disturb as many roots as possible.
After the garden is planted and the seedlings are up, mulch heavily between the rows to reduce weeding and retain moisture. We like shredded leaves; others use grass clippings or straw. Just remember that grass often has dandelion seeds and straw may be contaminated with pigeon grass, hoary alyssum, and who knows what else.
Plastic weed blockers are also good at reducing weeds while allowing moisture to penetrate. The only disadvantage is the yearly cost, the need to stake it down and disposal.
Mow away from gardens or flower beds. Installing wood, concrete, or plastic edging helps stop the invasion of quack grass and other weeds. Flame weeding is another technique that works very well for certain weeds but has to be done carefully to avoid collateral damage.
If you use commercial fertilizer on your vegetables, fertilize in bands next to the plant rather than broadcasting over the entire garden. That way the nutrients are there for the plant you are growing but not for the weeds in between.
Solarization is a chemical free method to prepare a new garden spot. First, mow any weeds or grass very short and cover the plot with clear plastic. Seal the edges with soil, bricks or boards to prevent leakage. After a day in the sun the temperature under the plastic can reach 140 degrees or more, effectively killing grasses and weed seeds. This is a slow process however, expect it to take more than two weeks.
The last advice is the hardest; plan to get down on your knees and pull weeds growing in the rows on a regular basis. It is just too demoralizing to let them get ahead of you. Like Santa says: hoe, hoe, hoe!
These local garden articles will reach you each week throughout the gardening season, but also click on "Yard and Garden” at the University of Minnesota Extension website -- www.extension.umn.edu -- for gardening information, or visit our Facebook page at www.facebook.com/Beltramicountymastergardeners.
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