Mulch is on my mind right now. Knowing that there is only so much that one middle-aged, menopausal woman can do, I enlisted help in mulching the entire property for the garden tour. This hard-working crew from a well-regarded local garden/design firm was "all over our yard like spider monkeys", according to my daughter.
Approximately five hours later the rain started, a biblical type of precipitation that proceeded to wash out entire sections of mulch and send it down the walks and lawn like little brown rivers tinged with big green dollar signs. Believe me, it was like one of those Arizona-style arroyo carvers and a tropical monsoon all in one. Oh well, stuff happens. There's another one predicted for tonight.
But back to the mulch. It's also been a hot topic on the Master Gardener online discussion board, cypress mulch to be exact. But first, what is mulch good for?
- Keeps soil temps even and moderated
- Suppresses weed growth
- Prevents soil compaction
- Improves water absorption by preventing soil crusting
- Prevents mechanical damage around trees and shrubs
- Looks attractive and gives landscape a consistent appearance
- Improves soil structure as it decomposes
Back in the day, mulch was made with whatever was at hand; indigenous materials that were cheap and abundant. Then somewhere down the line, people decided to exchange mulches in trade to aid commerce. Before you know it there's a whole endangered cypress swamp sitting in bags in the parking lot at Home Depot or what have you.
Back in the day when you picked up a gardening book to find gardening information, it might tell you to use salt hay as a mulch. And you wondered what the heck? Lots of gardening books were written on the east coast for a national audience yet didn't go beyond a regional scope. Maybe it's time for our mulches to back to the regional approach.
What's the best mulch to use?
- Leaves; ground leaves are good, whole leaves (or "lazy (wo)man's mulch") can tend to mat, but I still throw them into the borders during fall. They feed the soil as they break down. Leaf mold is better as a soil amendment because it can crust.
- Dried grass clippings are readily available, fresh ones may burn plants.
- Pine straw is attractive and water permeable.
- Pine bark comes from a sustainable source, looks good, but larger pieces may float
- Hay has thousands of weed seeds, best to avoid.
- Straw is good for vegetable gardens but there can be some weed seeds. It breaks down fast.
- Groundcovers make for great living mulches and are underused when they can make for a permanent low maintenance mulch once established.
Coarse shredded pine bark The Garden Buzz
Mini-nugget pine bark The Garden Buzz
Pine straw looks attractive, is permeable The Garden Buzz
There are other materials like rice hulls and cocoa bean hulls being used lately. Cocoa hulls can be toxic to dogs and expensive to use. But if you like your garden smelling like a Hershey bar...
Oyster shells are a common sight in coastal states. Rock mulches are used in many places but are notorious for weed problems and become embedded in soil. They sometimes heat up the soil. Landscape fabric underneath can cure this, but is hard to work with if you are constantly putting in new plants.
During spring break, we traveled through inland Florida and out to the "Forgotten Coast" to Apalachicola. We drove through hundreds of miles of swamps, that were alive with animals and blooming with flowers. then we came upon a plant manufacturing cypress mulch and I felt a little queasy. I won't be using cypress mulch anymore. It's tough when people's livelihoods are at stake I know. Jobs come and go, but there are no new cypress swamps being created.