Ask the gardening expert, July 2

I am starting a new garden at my new house. The garden will be on a slight grade. I am using landscape timbers to level it, so most of the garden will be elevated. I would like to know what I should mix with the clay to make my garden flourish this summer. The soil is rather wet, but workable, it has a reddish color and is a bit stiff. Should I use sand or peat moss?

First of all, only work in your clay soil when it is reasonably dry. If you work it while it's wet, it can set up like brick, and you'll need a sledgehammer to till your garden. Organic matter, and lots of it, is the best cure for clay soil. If you can find a supply of aged livestock manure, compost or leaf mold, it's usually cheaper than buying peat moss. If you don't have a compost pile, I suggest you start one so you'll always have your own source of "black gold." Add all your lawn clippings, young weeds (but no weed seeds) and veggie table scraps to the pile. There's no better food for the soil than compost, and healthy soil means healthy plants. Mulch your plants for weed suppression and soil moisture management, and as it decays, it will also add to soil health. Introduce some earthworms, too. They'll "till" the soil constantly and incorporate the mulch and other matter. But you should have the soil tested before adding it. The Master Gardeners at the WSU Clark County Extension office can help you with testing information and will give you a free kit. In that kit there is an information sheet that will help guide you in doing the soil collecting. The lab charges according to the crop you are planning. For more information contact the Master Gardeners at 11104 N.E. 149th St. in Brush Prairie, or call 360-397-6060 ext. 7725.

Celeste Lindsay is a WSU master gardener. Send questions to lindsay8@pacifier.com.