In early spring, everything comes awake in the garden. Perennials are just starting to send out new buds and shoots, lawns are starting to green, and the weeds—the bane of every gardener’s existence—are really coming to life. Spring is a great time of year to spray weeds before they have had a chance to really get established and develop a strong root system. However, you need to consider weather conditions and other factors before you get out in the yard and start spraying.

We’ll explain the best times to spray weeds in spring and when to wait for a better day.

Why Spray Weeds In Spring?

Weeds that are more established in summer are much tougher to tackle. You may spray them only to find the plant re-sprouting from the base. In many cases, a combination of cutting, pulling, and spraying becomes necessary with well-established weeds.

If you overlook them, weeds can release massive amounts of seeds once they flower, which means they’ll spread significantly this year or next. Tackle problematic weeds in spring before they get the chance to go to seed and take over your garden.

Best Time To Spray Pre-Emergent Weed Killers On Lawns

Pre-emergent herbicides are used on lawns to prevent weed seeds from germinating in spring. These weed killers are usually applied in early spring in the South. Treat your lawn once soil temperatures reach 50 degrees Fahrenheit when many weed seeds sprout. Timing is critical here, as pre-emergent herbicides won’t work on weeds that have already sprouted. Crabgrass will germinate once the soil surface reaches 55 degrees for four or five days.

Best Time To Spray Weeds In The Garden

If you use a weed killer like glyphosate, you’ll have the most success when weeds start to emerge in spring and have a weak root system. Weed killers like Roundup work best during warm, sunny weather above 60 degrees Fahrenheit. This is because weeds are actively growing and will absorb more of the chemicals. At the same time, don’t spray when it’s too hot—above 85 degrees—or a weed killer may evaporate and dry too quickly.

The best time to spray is in the morning or late afternoon when the weather is calm. If there is a light breeze, make sure the weeds are downwind of your sprayer instead of your prized flowers. Don’t spray on a windy day or when rain is in the forecast, as it will wash the weed killer away.

Best Time To Spray Natural Weed Killers

If you’re spraying around the vegetable garden or have concerns about the toxicity of weed killers, use a natural weed killer instead. Natural weed killers use vinegar, iron, or essential oils to kill weeds. (Don’t assume homemade weed killers made with salt and vinegar are better, as the salt poisons the soil and prevents all plants from growing.) Natural weed killers may not be as effective with one application as they generally don’t kill the roots of plants. The same rules apply when spraying natural weed killers: Wait for a warm, sunny, calm day.

Alternatives To Spraying Weeds

Of course, good old-fashioned hand pulling is preferable where possible. It’s essential to dig out the whole plant, as some weeds have roots that break easily, causing them to send up lots of new shoots. Focus on weeds that have started flowering since you want to interrupt their reproductive life cycle.

If you have a few scattered weeds in your lawn, it may be easier to mow them to keep them in check. Some weeds, like clover, can be beneficial to lawns, while others are more invasive and can take over your yard unless you remove them.

Other alternatives to spraying include laying down cardboard or dark plastic to suffocate weeds, though this can take weeks to kill off weeds. A quicker approach is to cover weedy areas with cardboard and then add a layer of mulch on top.

Finally, adding more desirable plants can help with weed control. Do what you can to outcompete the weeds, and keeping your garden weed-free won’t be such a big job.