How to Survive Grass Pollen Allergy Season in the Northern U.S.

Symptoms, When to Be on the Alert, Actions to Take

Grass Pollen
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The grasses people use in their lawns up North are different from the types used in the South, so the timetable Northerners need to follow to deal with allergies from grass pollen will be different than that for Southerners. Happily, there are ways that you can minimize your exposure to grass pollen and enjoy your summer in comfort. 

Allergic symptoms include:

  • Sneezing
  • Coughing
  • Itchy eyes

See a doctor if you experience these symptoms in late spring or early summer. Allergy tests are available to find out if it is only one type of grass that is causing these symptoms, in which case you could avoid growing that type of grass in your lawn, but it is more likely that you are allergic to all or most of the grasses in your area.

​​Worst Offenders and When to Worry About Them

To learn when grass pollen allergy season comes, let's outline the growth and reproductive stages that the cool-season types of lawn grasses undergo annually. The time of year that you need to worry about is the flowering part of the cycle.

"Cool-season grasses" are called that because they conform to a specific growth cycle, in which they grow most actively in the spring and fall in the North, when the weather is neither hot nor cold, but "cool." They go dormant at some point in the summer (without a lot of hose-watering on your part, the use of an automatic irrigation system, or enough rain), to cope with weather that is too hot and dry for them. Dormancy is a plant's way of "taking a breather." In autumn, grass plants will perk back up again, but the fall lawn puts more energy into such things as storing nutrients for winter than in flowering.

To understand seasonal allergies, we must focus on the earlier parts of the cycle. As the snow recedes in the North in spring, the cool-season grasses start to grow actively once again, pushing up green shoots. From these shoots, flower stalks will emerge at some time in May. Flowers will follow. The average person may not think of the grass in a lawn as ever "flowering" and may speak, instead, of the grass "going to seed," but it amounts to the same thing: Grass must first flower before it can go to seed.

Kentucky bluegrass is one of the worst offenders among the cool-season grasses used in the lawn. Unfortunately, the problem is not restricted to lawn grasses. The following types of grasses are not used in lawns but do produce a pollen that causes an allergic reaction:

  • Johnson grass (Sorghum halepense): an invasive plant considered a weed
  • Orchard grass (Dactylis glomerata): a grass of pastures
  • Timothy grass (Phleum pratense): a grass used for hay

Reproductive activities occurring in the flowers of these plants and others will be a factor for sufferers of grass pollen allergy for several weeks in the North, spanning the following months:

  • End of May
  • June
  • Beginning of July 

How to Combat Grass Pollen

Here is some extra incentive to mow the lawn, a task many homeowners find annoying and/or boring. A well-maintained lawn will not contribute to problems with grass pollen allergies because flower stalks are mowed down before flowers can develop. But non-lawn grasses and grass in neighbor's lawns that is not mowed regularly will still plague sufferers from grass pollen allergies (you have only so much control over your environment).

If you suffer from grass pollen allergy and want to try to minimize exposure, you can:

  • Mow often: The recommended mowing height is when the grass is 3 to 3 1/2 inches tall. Be faithful about mowing your lawn when the grass reaches this height. Do not let the grass come into bloom.
  • Wear a face mask when working in the yard May through July, in case your neighbors are not so faithful about mowing and allow their grass to bloom.
  • Consider removing your lawn using a ground cover in the space, instead. For example, in some cases, moss or clover can substitute for grass. You can walk on them just as you would a lawn. If you do not care about having something that you can walk on, then you have even more choices, including attractive, flowering ground covers.