The Grass Doctor

Why is patches of my Lawn STILL Yellow After doing all these things?!?

I live in the North (in Ontario, Canada) and my grass type is a mixture of Kentucky Bluegrass, Fescue, and something else... My lawn looks green but once i cut my lawn back to its 2.5 inch height it reveals several spots of yellowing on the lawn. It seems the green part of my grass HIDES the yellowing parts when it grows (like a canopy). The yellowing seems to have been caused by winter damage (is my guess) or maybe something else (?). So far i've tried: 1. Aerrating 2. Fertilizing using Scotts' Turf Builder (29-3-4) 3. Raking out dead grass 4. Mowing the lawn to 2.5 inches 5. Watered: 1 inch per week We have been receiving lots of rain here in SouthWestern Ontario region (near Toronto). And i have an extension sprinkler system in place. My lawn has definitely received its required 1 inch of water per week but still those yellow spots dont change. It seems like they are DEAD! Is there ANYTHING i can do to repair the yellowing or must i dig it up and reseed those areas

Public Comments

1. Do you have toilets in Canada ? If so use that instead of the garden !
2. your landscaping could use planetary saving ecological options instead of the news -spin consumerism of the republican golf association! go for a walk ....! in natural local environment and pick the most appealing ground cover available or start growing smokeable grass!
3. In the UK this can be caused by leatherjackets - grubs that eat the roots of the plants. You could try an insecticide on the yellow patches followed by re-seeding.
4. I think maybe you should get some topsoil and put there and replant the grass on the new topsoil. There might be a possibility that there are a type of bug killing it. ( I recommend going to your feed store and tell them about this and they will get you hooked up with the right thing ). My neighbors grass looks just like you are describing yours to be. I don't know what's wrong with theirs either. Ours is really green and theirs is yellow. Maybe the sun is scorching it. ? ..
5. If you have a female dog, their urine causes similar problems to yours. Scarify or hard rake, add some fine soil top dressing and water when dry. Also if possible dig up a small section and check for soil borne pests ( leather jackets/ chafers/ wireworms) as root damage from BELOW often causes such complaints.
6. You're cutting your lawn too short. Your lawn is growing very rapidly because it's a cool season grass and cool season grasses grow the fastest in early to mid spring. Also, in early spring, lawns tends to grow unevenly. The denser, faster growing clumps block the sun to the lower part of the grass. When you cut at 2.5" you remove the green portion of your denser, longer grass clumps leaving yellow patches. When your fertilizer kicks in (with warmer temperatures, especially if you have used a slow release form of nitrogen that requires microbe activity to break it down), you will get a more even growth rate. You will also see a more even color after cutting. Raise your mower to 3". Kentucky Blue & rye grasses are best cut at 3 - 3.5". I've had the same problem. It has been fixed by raising my mower height to 3" and the grass is starting to slow its growth rate. I have more uniform density and now my lawn looks an even green after cutting. Good luck. P.S. Not likely disease if its green before you mow and then yellow spots after you mow. Also, not likely it's bugs or dog urine if it's healthy green before you mow. All of these should show when the grass still needs to be cut.