If you truly want your flower garden to be as weed free as possible, plant the garden in small sections. Use a thick layer of newspaper, at least eight or nine layers, or a single layer of cardboard, covering the soil between the flowers or perennials as you plant them.
Then apply at least 2 or 3 inches of a good mulch such as pine bark, hardwood bark, etc. over the cardboard or newspaper. Do not use compost, because weeds will easily grow in compost, so you want compost under the cardboard, not on top of it.
But, but, but . . . these things are temporary. They only work for so long, then as they decompose, the weeds have a chance of growing again. But the upside is that as they decompose they actually improve the quality of the soil in your flower garden. To really stay ahead of the game, you should apply a new layer of mulch each season.
Pre-emergent applications do work at controlling weeds, but do not kill existing weeds. They prevent weed seeds from germinating. So in order for them to really work, you have to start with a flower garden that is completely free of weeds. If you need to make a second application, pull any and all weeds first.
The secret to making all of this work?
Diligence my friend. Diligence and perseverance. You mow the lawn about once a week, right? Weed the flower garden on the same day, every single time you mow. It should take you about 60 seconds, and while you’re at it you get to admire the beautiful flowers. If you see many weeds, make another application of mulch.
Sunlight. Flowers love sunlight, but so do weeds. The secret is to give the flowers plenty of sunlight and the weeds none. As the flowers, especially perennials, grow to a larger size, they do a great job of blocking sunlight to the soil. Weeds hate that!
If you have a flower garden that is completely full of beautiful perennial flowers, the weeds won’t have a chance. Even if they do germinate under the canopy of the flowers, they will be small and spindly, easy to pull. Thanks to Mike McGroaty for help with this article.
If you have other questions about your garden or landscape, feel free to contact a Master Gardener at the University of Illinois Extension office in Charleston at 217-345-7034. You can also check out the many horticulture webpages at the U of I Extension’s website by visiting http://web.extension.illinois.edu/ccdms/ . And be sure to like the Master Gardeners’ new Facebook page, at www.facebook.com/ColesCountyMasterGardeners.