Warm weather and cool weather weeds rear their ugly heads each season in our turf. One weed plant in your turf now has the potential to be 1000 weed plants in your turf next year. Weeds are thieves! They steal compete with your plants and turf for nutrients, water, and oxygen. Prevention is the best control for weeds. Today we’ll focus on the timely application of weed pre-emergents and some other options for battling these pesky, unwanted, invading plants.
What are Weed Pre-Emergents?
Weed pre-emergent is a granular herbicide that you apply to your turf by using a rotary or drop spreader BEFORE weeds are present. The product creates a chemical barrier in the top layer of soil which prevents the seeds of weeds from germinating and developing into a plant. Weed pre-emergents are one of the absolute best ways to prevent a weed invasion from taking over your turf. Applying this product in a timely matter is crucial. when it comes to pre-emergents, applying the product a little early is better than applying the product even one day too late.
 Reminders about weed pre-emergents:
- Pre-emergents do NOT kill current weeds in your lawn. They only prevent weeds from germinating.
- Pre-emergent weed products should be applied each fall and spring season. Because we have both cool-weather weeds (the weeds that you see in your lawn in February and March) and warm-weather weeds (the ones you see summer into fall), we have to be diligent about being ahead of the game with our prevention. Spring pre-emergent is generally applied at the end of February into early March (after the first or second good spring rain). Fall pre-emergent is generally applied at the end of August through early and mid September (after the first real September rain is ideal).
- You MUST read the instructions on the pre-emergent product label. Get to know how to calibrate your spreader, calculate the area you need to apply the product, see if the product needs any subsequent applications and follow up in a timely manner if so.
- Look for these named pre-emergents at Rainbow Gardens:
- Dimension: treats grasssy weeds
- Gallery: treats broadleaf weeds
- Crew: treats both grassy and broadleaf weeds
If you don’t plan on using a pre-emergent to control the weeds in your turf, be ready for a battle. We generally don’t recommend post-emergent products because most people don’t apply them correctly and end up damaging turf, damaging surrounding plants, or ending up with a less than desirable result. So if our pre-emergent advice goes unheeded, the following options are your next best bets for a weed free, healthy lawn.
Other Options for Weed Control in Turf
Mow and Bag: A consistent schedule of mowing and bagging grass clippings can go far in the battle of weeds. Mowing and not bagging does not do you much good because there is a possibility that weeds have gone to seed and the seed will get left behind on the soil and germinate. Bagging removes the plant and seeds, eliminating the threat of the weed developing.
Keep A Watchful Eye: There is a saying that your shadow is your garden and lawns best friend. Don’t let the weeds even grow. If you neglect paying attention to your lawn and by the time you go out to observe it, you see large weeds with flowers, you’ve basically blown it for the year. Sorry but it’s true. By the time you see flowers or seeds on a weed, there is likely more that have already spread themselves around your turf. Don’t let them grow in the first place!
Put Your Back Into It: When you’ve missed out on applying your pre-emergent, get ready for some old-fashioned hand-pulling. While this method can be taxing, it is also effective. Small weeds are easier to pull than big weeds. The roots aren’t anchored in as deep and if you get to them when they are small, they also haven’t developed seeds yet.
Repel Weeds with a Healthy Lawn: Another way to lessen your chance at developing weeds in the first place is to create a healthy, lush turf with a maintenance of proper fertilization and proper watering and mowing. A healthy, dense lawn can choke weeds out and not even give them a chance to encroach. Follow our lawn fertilization schedule and get on the path to a weed-free zone.
So remember, timing is crucial. Come see us at Rainbow Gardens for the pre-emergent that fits you needs best…and don’t delay!
~The Happy Gardener, Lisa Mulroy
Thank You for the Information . It was very helpful . Tired of pulling Weeds .
Absolutely Kris!
We are tired of pulling the weeds too! Good luck with the battle and thanks for reading!
Excellent information. Thanks for the tips
Thanks Jan!
Appreciate you taking the time to read and give us feedback as well! We really appreciate it!
I am using pro diamine 65 WG, can I split this spring treatment into 2 separate treatments
As per label I was able to pull up for pro diamine 65 WG,
“Application Timing and Rate – Turfgrass
PRODIAMINE 65 WDG may be applied as a single application or in sequential applications
to control weeds germinating throughout the year. All applications should be made before
target weeds germinate. PRODIAMINE 65 WDG will not control weeds that have already
emerged.”
We recommend always reading complete labels when applying any type of herbicide, fungicide, pesticide, so that you are fully aware of all instructions, cautions, etc…
Hope this helps.
My prodiamine is to be put down when soil temps reach 70 deg. But experts say to put down preemergent now in early Sept for fall application. This is contradictory and confusing. Should I put down a preemergent with no soil temp restrictions?
Thank you.
You may need to contact the product manufacturer to get a better answer. We do not carry any products with prodiamine as the the active ingredient. However, products like Amaze, Dimension, and Gallery are fine to put down now. We generally advise to follow the label on specific products for best results. If the label specifies a soil temperature, it is probably best to follow that requirement.
Hi Lisa,
Just reading through your pre-emergent and fertilization pages and wonder if it is too late to apply a pre-emergent. I have both broad-leaf and grass-like weeds and leaning towards Amaze.
How long does the protection from the pre-emergent last? I’ve read some sites where it says that say putting down fertilizer after a pre-emergent disrupts the barrier from the pre-emergent. So when I apply an 18-6-12 to my Bermuda next month, is it going to break the barrier of the pre-emergent?
Thanx for the help and great read.
Hi Theo.
It is still time to put down pre-emergent. As a matter of fact, we generally advise to do it in fall after the first true rain, and we just had that (and more to come this weekend). This pre-emergent is for those weeds that germinate and grow in spring, so you will not have to apply pre-emergent again until Feb/March when you will do so to prevent the weeds that you probably are currently seeing in your lawn now. You apply pre-emergent for the future seasons. Applying your fertilizer mid to late October should not have a bearing on the pre-emergent if it is applied now. ALWAYS read your label on your pre-emergent and follow manufacturers advise for application (some do advise for a follow up application, but that is generally for the spring/summer applications). For your current weeds, you’ll need to oull them (easier after the rain) or spray for he broadleafed weeds (we have many options, and read the label to make sure they are safe for your type of turf). The pre-emergent only prevent new weed seeds from germinating, it doesn’t eliminate existing. Hope this helps!