May Lawn Care Schedule

May Lawn Care Schedule

Post updated April 25, 2020
Spring is here and in full effect! By now your lawns should be green, thickening up, and taking off. This how-to lawn care calendar is a month-to-month guide for cool season grasses, those with grasses like Turf Type Tall Fescue (TTTF), Kentucky Bluegrass (KBG) and Perennial Ryegrass (PRG).

Following LawnPhix’s monthly lawn care guide will help you kickstart your turf health, vigor, and color this spring, and set your lawn up for success this growing season.


Mowing your lawn is the single-most important lawn care task that you can control to build a thick, healthy turf. Get into the habit of mowing two to three times per week, especially in May when your lawn has come out of winter dormancy, and is actively growing. Between the frequent rain and warmer soil temperatures, the top growth of grass is at its peak. 

Try to mulch your clippings whenever possible. Never take off more than 1/3 of the grass blades at a time. For example, if you let your grass get away from you and it’s standing at six inches (6″), only take off the top two inches (2″), leaving four-inch (4″) grass blades. And it’s unlikely that 2″ grass clippings will actually mulch, so it’s probably a good idea to use your bagger to pick up that grass. Leaving long blades of grass on your lawn is not going to do any good – so bag ’em. 

Weed Prevention

Save 10 on Pre Emergents

If you used a pre-emergent in April, you can apply your second split application later this month as soil temps approach 65-70 degrees. Always read the labels of these products, and make sure you stay within the annual limitations. Example, I put down prodiamine at 3lbs./1,000 in early April when my soil temps were are around 50 degrees. I’ll add a second application ~40 days from my first application, leaving me within that maximum annual application rates.

Dithiopyr and Dimension has some post emergent herbicides that will kill crabgrass and dandelions up to the three-leaf stage. I’ll be putting one of these down in May. 

Spot Spraying Weeds

You’re probably seeing some annuals and biennials appearing. SpeedZone is a terrific choice for spot spraying. Read the label! Generally we’re safe to apply this at any time throughout the days in May, but it’s still advised to use these products in the morning, after early evenings. Personally, I’ll be applying Quinclorac on my crabgrass and clover.

Another big problem that I hear about often – and one that I have myself – is Poa Annua. Click here to read more about Poa Annua / Annual Bluegrass. And for a detailed post about weed control, read How To Get Rid of and Control Weeds in Your Lawn.


Now is the time to really juice your lawns with some food. As long as you didn’t add a Pre-emergent with fertilizer during you April lawn care plan, you can go 1/2 – 3/4 lbs. of Nitrogen per 1,000 ft2 in the next 4-6 weeks here. Milorganite is always a good option, but since the prices can be high and inventory scarce, there’s plenty of Milorganite Alternatives. Go for a full rates in the first week of May.

If you didn’t add a winter fertilizer, and didn’t apply fertilizer in April, then apply a half rates of both  organic fertilizer and a starter fertilizer. The goal here is to get some nitrogen down into the ground now before the dog days of summer arrive.

To calculate the amount of nitrogen per 1,000 ft2, be sure to be sure to use my free nitrogen calculator.


Always a great idea to incorporate both humic acids and micronutrients into your lawn care plans. These, unlike your standard fertilizers, are generally safe to apply during the hot summer months. I’ve been using Kelp4Less Extreme Blend and Organic Humic Acid recently and am very pleased with the results. Each of these powders are under $20/lb. (with coupon codes) and can be easily mixed for backpack sprayer applications. 

For a new all-in-one option, Kelp4less Green Lawn & Turf contains Extreme Blend, Humic Acid, Molasses Powder, and Iron Sulfate. Apply this to established turf as frequently as every two weeks, and 1-2 ounces per gallon per 1,000 sq. ft.


With the increasing outside temperatures, rainfall and humidity creates the perfect recipe for brown patch and other diseases. It’s still a little cool in early May, but be prepared and stay ahead here. Apply preventative rates of propiconazole or azoxystrobin in the first week of May.

Read how to prevent and treat brown patch in lawns for more details and products. 

Four Step Plan

Those who just want to follow a simple Four Step plan, your window is now for Step 2. Shoot for Memorial Day weekend and apply Jonathan Green Weed & Feed. Their 4-Step plan is the best on the market and I feel it’s much safer for your lawns – especially during the summer months – than say a Scott’s 4 Step. They really focus on feeding the soil first, which really is the name of the game here. 

May Spring Lawn Care Summary

  • Mow your lawn twice a week
  • Aim for 1″ – 1.5″ of total water each week. 
  • Put down your second split application of pre-emergent as soil temps approach 65-70 degrees (Memorial Day). Use Dithiopyr or Dimension for their post emergent qualities
  • Apply more organics such as Milorganite or Bay State at full application rates
  • Apply Kelp4Less Extreme Blend or Green Lawn & Turf
  • Prevent fungus/diseases by applying preventative rates of fungicide
  • Begin spot-spraying weeds
  • Check out our Month-to-Month Lawn Care Calendar 

Recommended Fertilizers & Spring Lawn Care Products



[quads id=2]



Leave a Comment