by Ron Stevenson,
Fergus Horticultural Society
The colour of our trees this year is absolutely exquisite. Our Canadian maples are truly showing their best colour in many years. This is a great family time for identifying leaf species and raking the lawn.
Carol Dunk, an avid horticulturalist, spoke to an attentive group at the Oct. 15 meeting of the Fergus Horticultural Society. Her presentation An Ode to Soil was a timely presentation concerning the composition and care of garden soil.
Dunk has great advice for handling those millions of leaves that fall on lawns. Rake them once they are brittle and dry. Leaves left on lawns cause many spring problems.
"But don’t get rid of those leaves. Chop them and put them on flower and vegetable beds. Chopped leaves are a treat for the soil in gardens. By spring, they’ll all be gone, if you chop them fine enough."
Dunk uses a Flowtron leaf chopper but she suggested that a weed whacker in a large garbage pail will do the trick. "Last year I put about four inches of leaves on the garden with great results."
If a weed whacker is not among one’s collection of garden tools, just collect half a bag of dried leaves and crush them inside the bag. The kids may find a good old fashioned pillow fight will break up the leaves nicely. Just make sure the leaves are dry and brittle.
Even if gardeners do not have the time or patience to chop up leaves, a blanket of leaves on the garden is invaluable. I tried using our lawn mower. I directed the discharge chute to blow out the chopped leaves directly onto the beds. That works great.
To make sure they won’t blow around, a good soaking will help. Remember this is the fall and those rains will soon turn into the white stuff. Moisture is essential in the chemical breakdown of leaves.
Excess leaves should be placed in the compost pile. Lots of moisture will help the decomposition.
All good gardens must be the home of earthworms. Lots of them. If gardeners do not see them on a regular basis, that garden needs compost. Compost and earthworms go hand-in-hand for garden success. This is the time of year to get lots of free humus (compost).
The major benefit of earthworm activities to soil fertility is threefold.
– Earthworms are essential to keep the soil loose and open. Due to its constant burrowing, they physically create channels which allow drainage and ventilation to occur. Those passages allow water and air to travel to the top 6 inches of the soil. Has anyone ever seen a group of earthworms on the surface after a heavy rain? The channels have been flooded and the worm has surfaced for safety.
– Earthworms convert large pieces of organic matter (dead leaves) into rich humus that improves soil fertility. Dunk said, "You can actually see the worm bring the pieces of leaves or manure down the channels. This is achieved by the worm’s actions of pulling down below any organic matter deposited on the dried dirt, either for food or when it needs to plug its burrow. Once in the burrow, the worm will shred the leaf and partially digest it, then mingle it with the earth by saturating it with intestinal secretions. Worm castings have 40% more humus than the top 6” of soil in which the worm lives."
– As well as organic matter, the earthworm also ingests any soil particles that are small enough to fit into their gizzard where fragments of grit are ground. When the worm excretes that in the form of castings, which are deposited on the surface or deeper in the soil, minerals and plant nutrients are made available.
The best way to increase the levels of worm population in the soil is to avoid the use of synthetic chemicals.
Agricultural chemicals such as salt based fertilizers, pesticides, and herbicides can kill earthworms.
Even if a few pesticides do not kill earthworms, birds are killed when they eat those worms.
Adding organic matter, preferably as surface mulch, on a regular basis will provide them with their food and nutrient requirements, and also creates the optimum conditions of heat (cooler in summer and warmer in winter), and moisture to stimulate their activity.
Dunk suggested tilling the soil as little as possible. Tilling dries up organic matter which is the earthworm food.
To increase worm numbers, limit pesticides, minimize (or no) tillage, and keep the soil moist and rich in organic matter. Those are earmarks of good gardening.
