Saint Augustine grass is a major concern when it becomes overgrown, and if the lawn is not managed or mowed properly when it is in an overgrown state, a St Augustine grass lawn will become at high risk of either dying in places or dying altogether from severe lawn mowing practices in cutting back too much leaf material or thatch at once. Great care must be taken when mowing an overgrown Saint Augustine lawn, as there is great risk in mowing these lawns too short.
Why Mowing Overgrown Saint Augustine Is A Problem
Saint Augustine grass is a warm season grass type, and while most warm season grasses have both Rhizomes (below ground runners) and Stolons (above ground runners), Saint Augustine grass is quite unique in that it only has stolons.
When grasses grow higher, their crowns also raise higher, and crowns are the life-centre of all plants, including our lawn. To remove the crown of any plant, will mean the death of that plant, including our lawns in whatever area of the lawn is so affected by this loss, unless the lawn has an underground source of crowns to regenerate from.
Lawns such as Bermudagrass or Zoysiagrass can be mowed a little more severely, and still successfully recover at a better rate than Saint Augustine lawns can, because they have their underground runners (rhizomes) to help the lawns recover.
However, a Saint Augustine lawn cannot do this, it has no rhizomes to assist it in recovering from any severe scalping. If a Saint Augustine lawn has its crowns removed, it will die in the affected areas, and will need to recover from surrounding healthy areas of lawn, which will spread into the dead areas of turf.
And that's why Saint Augustine grass can be such a problem to de-thatch, while many other lawn types are not.
Lower Saint Augustine Mowing Heights Over Time
The best method to safely reduce the height of Saint Augustine grass is to do it slowing in stages over time, and over many lawn mowings.
This way, the Saint Augustine grass will re-train its crowns to grow at a lower height, and the lawn will not die. When a Saint Augustine lawn is being re-trained to grow at a lower height, expect some small areas of turf to possibly die away, this cannot be helped. However, if we're careful these instances should be greatly reduced and easily recovered from.
The Process Of Lowering Mowing Heights
Begin the first lawn mowing at a very high height., it will not look like a masterpiece after cutting, but it's a start on our road to recovery and the lawn will not die.
Frequent lawn mowing is very important at this time, if the lawn is left too long between cuts, the crowns will either not lower at all or will otherwise simply raise higher again, and the lawn will be scalped and possibly die if the height is reduced at the next cut.
In Summer time, and if the lawn is in good health, reduce the lawn mowing height one notch at a time every week to two weeks. If mowing every week, keep the same height over two lawn mowings.
This lawn repair is most effective during the active growing season when the weather is warm.
Over subsequent lawn mowings, slowly reduce the lawn mowing height one notch at a time on the mower. The key is to take it nice and easy, and do things slowly. Patience is key.
The crowns of the Saint Augustine lawn will re-train themselves to begin growing at a lower and lower height, safely, over time.
Finishing Off and Getting Rid Of Thatch
To finish the re-training process of the lawn crowns, simply continue lawn mowing at regular intervals, and the lawn will eventually fully recover and look green and lush once again.
Any small areas of Saint Augustine turf which did possibly die off or become stresses in the process should have recovered by this time.
If we have excess thatch in the lawn at this time, then this too can be repaired.
Ensure the weather is still warm and not entering into Winter. Repeat the same process as above, slowly lowering the lawn mowing heights over time.
Once the Saint Augustine thatch has been reduced and the lawn is still green and healthy, it's time to increase mowing heights to optimum lawn mowing heights for Saint Augustine grass. And that’s our lawn thatch control also done, very easily and safely.