Weed and feed fertilizers are often used in combination with seeding. Weed and feed formulations consist of two components: a herbicide to kill weeds and a fertilizer to strengthen the turf. The herbicide will weaken the grass as well as the weeds and the fertilizer will strengthen the weeds as well as the grass. When applying seed over a weed and feed application, remember that some weed and feeds can prevent grass seeds from growing.
It is important to know what kind of grass you have growing or want to have growing. Certain chemicals act differently on different species of grass and weeds. For example, the common herbicide 2,4-D is toxic to some cultivars of St. Augustine grass (Stenotaphrum secundatum), which grows in the area roughly covered by U.S. Department of Agriculture plant hardiness zones 8 through 10. Another common herbicide, atrazine, is potentially lethal to grass when applied in temperatures above 85 degrees Fahrenheit. Use the instructions on the bag of each weed and feed product to determine how it will affect seeding.
Types of Herbicide
Herbicides can target weeds before they germinate from seed – pre-emergent – or as developed plants – post-emergent. Before you seed, you can use a non-selective, post-emergent herbicide to control any weeds in the area to be seeded. Most of these can be applied up to two weeks before seeding to control any existing weeds. Herbicides should not be used after seeding until the new seedlings are established. Mowing and spot treatments can be used to control weeds until the seeded area is actively growing and requires only maintenance watering. Establishment times vary depending on the type of seed you use and your weather conditions.
Only use a weed and feed if the weed infestation is completely uniform over the entire lawn and all species of weeds targeted will be affected by the herbicide in the weed and feed. This scenario doesn’t occur often, so it is more likely the use of an herbicide and a fertilizer separately will be needed. If the weeds are uniformly spread over the area to be treated, match the appropriate weed and feed product to your grass, the seed you have recently applied or want to apply, and the time of year.
It’s important to know a little about herbicides so you can make the best choice for when to apply seed in an area that has been treated for weeds. The most common types of herbicide in weed and feed products are selective and systemic. Selective herbicides target a species of plant to kill while systemic herbicides work by being absorbed though the roots and then transported throughout the plant, killing it from within. Read the bag label to see what kind of herbicide is used in the weed and feed you are considering using or have used. The bag label will tell you how many days you must wait before applying seed to a lawn that has been treated with that product.
Once your grass is looking healthy, keep it in shape with a Best Buy lawn mower and grass trimmer .
Moss thrives in the shade and you’ll often find it growing under trees. Consider cutting back some of the lower branches, thinning the coverage and letting more light through. If it’s compacted, pushing a garden fork into your turf every 15cm or so will get some much needed air back into your grass. This will also help prevent moss. You should regularly move heavy items around the garden, so the grass underneath can get a breather. And if you’ve been using moss killer then remember to rake away the dead moss. You’ll need to seed the bare patches with more grass otherwise the moss could simply re-grow. Help the new grass grow quicker by adding some top dressing to the bare patches.
Best lawn weed killers
We’ve tested several lawn treatments from top brands, including Scotts and Evergreen to see if there’s any lawn treatment that’s an excellent all-rounder.
Whether you’re struggling to control moss, weeds or both, there’s lawn treatment that can help, but they don’t all do an excellent job. Some will work wonders for your grass, but not make a dent in the weeds and moss, while others do a better job at controlling your weeds than improving your grass.
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