Controlling Crabgrass: Will I get crabgrass this summer? In almost 40 years in the lawn industry, I have never seen such unusual spring weather than this year. Cold, wet and then warm …repeat, Mother Nature couldn’t make up her mind!
In the last few weeks many have asked “Is it too late for controlling crabgrass?” Well, the weekend weather has limited our time to apply lawn products; hopefully you were able to apply Green-Up with Crabgrass Preventer in April or in May. Remember, crabgrass germinates over a long period of time, not just when the forsythia blooms. There are many factors that contribute to controlling crabgrass. First, crabgrass only grows in sunny areas of the lawn. Soil and air temperatures can affect how quickly crabgrass germinates. Disrupting the soil after applying crabgrass preventer by raking the soil or kids playing on the lawn can open the floodgates for crabgrass to establish. There are potentially millions of crabgrass seeds in your lawn. They just need to get to the surface, get some warm weather and sunlight and they can take off.
It’s now June, if you apply Crabgrass and Weed Preventer now you may get some crabgrass control. Note that I used the words “may” and “some” meaning do not expect 100% control! If you are not interested in trying to prevent crabgrass anymore this year, the best way to curb crabgrass growth is a healthy, thick growing lawn. Feed your lawn and apply grass seed to get grass growing in thin areas before crabgrass blades actually start to show up in July and August. The level of crabgrass establishment will also depend on the weather. If it is a scorching hot and dry summer and your lawn goes dormant or dies, the crabgrass will thrive. Remember, we can’t predict Mother Nature so we have to prepare before the wrath of summer weather arrives. This means following a sound lawn care program starting last fall with feeding and seeding your lawn.
The next problem is what about dandelions? They seemed to come out for a day and then disappear with cold weather many times this spring. Control of broadleaf weeds usually happens in May but again the weather confused us all as to how and when to control these weeds. As long as early summer weather does not become hot and dry you can effectively control broadleaf weeds. Temperatures over 85 degrees and grass under stress from heat and drought are not times to try and control broadleaf weeds; you may injure some good grass. Broadleaf weeds have to be actively growing and exposed for best control whether you use granular or liquid control. Be sure with Green-Up Weed and Feed granules you apply to a damp lawn either in early morning when some dew is present or after you lightly sprinkle the grass for 5 minutes. This is best so the granules stick to the weed leaves for best control. Remember, do not mow 2 days before or after you apply it and do not water in after application or have rainfall in the forecast for 2 days after application. Broadleaf weeds can take up to 30 days to disappear from the lawn. The weed killer needs to be absorbed by the plant and then work its way down to the root system for compete control.
Large quantities of broadleaf weeds can be present because you have low soil pH. Lawns thrive when the soil pH is between 6.2 to 7.0. Apply Mag-I-Cal for Acidic Soil to raise soil pH levels. Soil test kits are available at most stores or contact your local Rutgers Cooperative Extension office for a soil test kit. This provides a complete analysis of your soil to avoid future disappointment with your lawn applications.
Now it’s time for you to enjoy your first trip to the beach or have a picnic on your picture perfect lawn (I hope!).
Can I apply Crabgrass Weed Prevention and Green Up Weed & Feed in the same day ?
You can apply Crabgrass and Weed Preventer and water it in and then apply the Green-Up Weed & Feed to the still wet lawn.
I applied Green Up Weed and Feed (Yellow Bag) and I still have weeds about a month later. Can I re-apply again in beginning of July? I live in NJ.
Jim,We caution the use of this product when temperatures are over 85° as lawn burn could occur. Wait until temps have been below 85° a couple of days before you want to apply it and will remain below 85° for at least 2 days after application. Water in after 48 hours.
I live in NJ. I want to switch to your Organic Fertilzers next Spring, starting with Corn Gluten Weed Preventer-Fertilizer. However, my backyard especially has been taken over by Crabgrass this year! I intend to heavily aerate-seed-water this Fall.
If I put your Corn Gluten Fertilizer down in April(possibly just prior to 55-degree soil Temps), how long do I need to wait until putting it down again to make sure I have the barrier coverage overlapped without burning the Lawn?
Doug,This can be applied every 90 days. If seeding, stop 90 days before planned seeding as to not prevent germination of grass seeds.
I just applied green up29-0-30 I have crabgrass goosegrass chickweed clover and oxalis growing may I use your lawn weed control or season-long weed preventer with no fertilizer? Or can I use both at the same time?
Lawn Weed Control can be used after fertilizer is applied. Apply to a wet lawn when no rain is expected for 48 hours and allow to sit undisturbed for 48 hours.
Should I put this down before putting down Black Beauty Lawn Repair?
Lawn Repair contains fertilizer so you don’t need to. Do not apply crabgrass preventer until the new seedlings have been mowed 3 times.
Yesterday I raked the lawn to remove leaves and sticks and fertilized it with Green-Up with Crabgrass Preventer. Then we had a very good rain last night with more rain predicted scattered tonight again. My question is, when can I have the lawn aerated?
Aeration can break the crabgrass barrier formed in the soil. We suggest holding off on that until September.
I used the crab grass preventer and green up this past spring and everything was good until mid july and I have crabgrass everywhere now. How long should the preventer last for? Any tips on what I can do to get rid of it or is it to hot now?
The Crabgrass Preventer plus Green-Up Lawn Fertilizer should last for about three months. You can use a weed killer such as tenacity to get rid of the crabgrass and then overseed this fall. The frost of winter will kill any remaining weeds.
The Jonathan Green Team