Oak Leaves Do Not Kill St Augustine Lawns – Oak Leaves are Good for the Lawn

Late winter during the time when Live Oaks drop their leaves, I am often told “Leaves are killing my lawn!” Well, that’s not what is happening. Leaves do not kill your lawn. Cutting the water back during cooler weather, wearing you lawn out by raking leaves and tree roots – that will kill your lawn - but Oak leaves are not killing your lawn.

Myth: Leaves are Killing My Lawn

---

This persistent myth is hard to debunk. Common scenario is that a home owner has a landscape with young oak trees. Years go by and the lawn looks great. Then as the tree matures and becomes 30’ tall the lawn has random weak spots. These weak spots are gathering places for Oak Leaves. The home owner sees leaves covering a dead spot in the lawn and assumes the leaves killed the lawn. The truth is the roots from the tree killed the lawn but you can’t see the roots below ground, you only see the leaves. So leaves get blamed for killing the lawn.

The Biology of Leaves

A fallen Oak leaf still has the look of an Oak Leaf long after it has fallen from the tree. Because Oak leaves have a durable outer shell similar to a crab shell that does not break down. It is a hollow empty shell of a leaf and has no negative impact on your lawn.

Of course if the leaves are several inches deep and remain on the lawn for weeks, then you could suffocate the lawn – but I have never seen that happen except where someone raked leaves into a pile. And when the pile of leaves was removed the lawn quickly recovered.

The Natural Processing of Oak Leaves

---

The natural organic method (and perhaps the easiest) for processing of Oak leaves in St Augustine lawns is to mow your lawn with a mulching mower. The mulching action shatters the oak leaves and allows them to fall into the canopy. Once inside the canopy, the oak leaves are composted by natural processes to provide nutrients, minerals and organic matter for soil microbes and the lawn.

Composting of Oak Leaves is Beneficial – Just Add Water

---

Two critical environmental conditions must exist to compost Oak leaves; A sufficient height of the canopy of the St Augustine lawn and Water. Both conditions are quite easy to achieve – mow as high as the mower will go and water as often as law permits (even during cool weather). Do not be tempted to mow low to mulch more leaves – be satisfied they have fallen into the canopy. Trust me, the leaves will obey the law of gravity and continue to fall deeper into the canopy where biological forces will turn them into mush.

Once the Oak leaves are composted they become beneficial – not harmful – to your lawn. Below the lawn canopy, next to the soil is a very biologically active area of your lawn. It is an area of active composting. Leaves and all types of lawn debris – including dust, pollen and other pollutants - are being recycled into nutrients for the soil and plants. The Oak leaves feed the composting microbes with a steady supply of organic matter and minerals (mainly Carbon).

A healthy lawn is good for you and good for the environment because it recycles Oak Leaves.