Posted on: Monday, May 31, 2004

HAWAI'I'S ENVIRONMENT
Gardens grow better with mulch

By Timothy Hurley
Advertiser Staff Wruter

Thank you very mulch!

No, really — mulch, thanks a lot. You are a recycling, environmental and gardening superstar. More people should take advantage of you.

Mulch is essentially anything that covers the soil to protect it, and it does some absolutely fabulous things in the garden landscape: It holds in moisture, controls weeds, reduces soil erosion, protects against soil compaction and moderates soil temperatures.

Organic mulches, including chipped-up tree trimmings, wood chips and chunk bark, are best. In addition to those other beneficial things, they add nutrients and organic matter to soils. Mulches also can be used around plants in the garden or as soft "paving" for garden paths.

Mulch can be purchased at local garden shops or directly from composting companies.

You can also find it free across most of the state. Availability can be tricky, so check with your county's recycling office for more information: on O'ahu, 692-5410; on the Big Island, (808) 961-8942; and on Kaua'i, (808) 241-6891.

On Maui, mulch is not generally free, because the county — in a move to divert even more from its landfill — pays contractors to mix green waste with bio-solids from sewage treatment to create compost, which is sold to the public. Maui County recycling coordinator Hana Steel says residents may be able to find some free mulch from a tree-trimming service, but she still recommends using the compost.

"Our volcanic soils need all the help they can get," she says.

While it's true a composted mulch is ideal, plain, old chipped-up tree trimmings will still do wonders. Experts at the University of Hawai'i Cooperative Extension Service say mulching will work for you to produce a healthier landscape — not unlike one that occurs naturally in the forest.

Think about it: Plants that grow in the forest are naturally mulched with a layer of fallen leaves, flowers, fruits and branches. Most plant roots grow near the soil's surface, and this layer helps protect the roots from drying under extreme temperatures. By applying mulch around plants and trees, you are imitating nature, recycling organic materials and improving the soil conditions that favor root development and plant vigor.

Perhaps the best thing about mulch is not having to weed as much, which leaves you more time to relax and enjoy your garden.

Thanks very mulch, indeed.

The UH Cooperative Extension Service has a free online publication: "Mulching for Healthier Landscape Plants" at www2.ctahr.hawaii.edu/oc/freepubs/pdf/L-3.pdf.

If you have a question or concern about Hawai'i's environment, reach Timothy Hurley at thurley@honoluluadvertiser.com, (808) 244-4880 or P.O. Box 156, Wailuku, HI 96793.