Dormant Summer Grass
Garden Clippings for June 30, 2018
My farmer friend who planted up our back forty wasn’t worried. The corn seed was sown at the end of May and in a week it began popping through the dry ground. We hadn’t had rain through the week but there was enough moisture in the ground to encourage sprouting.
Week two and still no rain. In the middle of week three we got a bit of rain, but hardly enough to keep the dust down. Finally, in the forth week after sowing seed, we received about a third to half an inch of rain. Then on a week ago Saturday, the 23rd of June, it rained cats and dogs all night long and kept coming down until mid-day Sunday.
My farmer friend was relieved. And thankful.
In the meantime, my backyard grass had turned the colour of a paper bag. The raised septic area was particularly awful looking, yellow, dotted with a few bright green weeds. Not to worry, I thought, because unlike my farmer friend whose yield is on the line, my dying grass issue was purely cosmetic.
The silver lining was that I skipped cutting the grass for two weeks.
When grass dries up and turns yellow due to drought it doesn’t die but rather enters dormancy. Essentially It goes to sleep and won’t wake up until the weather improves. In this part of the world grass always goes dormant before Christmas but will also do so in summer during a dry spell.
Grass going dormant is a result of its own natural defence mechanism triggering a slow down of growth to protect its roots and crown from over extending itself. During a drought, photosynthesis is put on hold until favorable conditions return.
Is grass in danger while it sits dormant? Turf experts might argue that grass is strengthened during a summer hot spell. Since there is no available moisture, grass roots are forced to go deeper into the soil in search of water. Deep roots mean strong roots that in turn are better equipped to feed grass blades as soon as favorable weather returns. Deep roots reduce the dependency on water, whether from above or from your sprinkler.
In our backyard I have found that as soon as a dry spell enters week three, seeds appear. Small spikes rise from the root zone and very quickly stretch above the yellowing grass blades. The seeds are difficult to see because of their small size and colour that blends with the turf.
Grass is not foolish. As soon as drought puts turf in stress mode, it switches its energy from producing grass blades to seed production. Its internal biological clock knows that stress might lead to death and new seeds are needed to ensure survivability.
How long can grass remain dormant without dying? In winter grass’s life is on hold for more than 4 months. Summer tolerance for dormancy is far less. In cool seasoned Ontario, we rarely experience a dry spell that persists longer than a month. And a good rain will turn grass from yellow to green almost overnight.
The obvious reason why we don’t like to see dormant grass in summer is because we admire green grass. Some would say that our society is obsessed in pursuit of a green lawn. Adding insult to injury are the resilient weeds with strong tap roots that contrast sharply with parched turf.
Next time you set your foot down on a patch of healthy grass, take a minute to stop and smell the roses. Grass is the most abundant plant we grow in urban centres. Grass keeps the ground cool, cleans the air just like trees do, and supports a multitude of healthy bugs, worms and other beneficial soil activities.