If your lawn is yellow at the beginning of the season there are a few things that may be causing this and I'm going to help you find a solution.
The solution of course is getting that yellow lawn to look green.
There are a lot of lawns that turn yellow during the summer. You may think it's because of heat, but most likely it is because of compacted soil.
This happens a lot in areas of the country where the soil has a lot of clay content. This clay or sold hardens as the temperature outside increases. And when you have hard soil it's also very hard for it to absorb water. And you know what happens to grass that doesn't get enough water, it yellows and dies. The grass needs water as it is an essential part of proper growth.
When the soil is hard the grassroots cannot grow as deep and the grass is not as strong. Fertilizers can help in that they feed the roots even as a shallow level. But even the fertilizer needs to penetrate deeply into the soil. When grass has shallow roots it is weak, more prone to bugs and diseases. So our objective here is to get the grass as strong as possible in the shortest amount of time.
The big problem is getting the soil looser. One way to do this is to aerate in the spring or at the beginning of summer time. Routine watering will keep the soil from drying out and getting compact again. Plan to aerate again in the fall to keep the soil from compacting over the winter season. And your grass will be a lot better for the next year.
Another reason for yellow grass is because there is too much thatch throughout the lawn. This cut grass builds up over the weeks of mowing and makes it difficult for water to get below the surface. If you have mulch or thatch more than 1/4 inch thick you need to get it out of the grass.
Now this procedure only needs to be done once every few years. There are attachments for modern lawn mowers and you can also use a rake. You will notice in short time that the grass will begin the takeoff and spread out and Greenup like never before. But if you still have a problem with yellowing grass, your soil might be a little low on nitrogen.
To fix this you need a fertilizer with a high nitrogen content. It's the first number listed on the fertilizer bag. A good fertilizer for nitrogen contains urea. You can also try using ammonium sulfate which has a very high first number. My choice is urea because it has a slower release time and lasts so much longer.