Grow Great Tomatoes in the NW
by Kirsten DeLara, Master Composter/Soil Builder
Wanna grow tomatoes? While we all dream of yummy home grown tomatoes, local gardeners are often challenged by our cool spring temperatures. The secret ingredients are heat and healthy soil. Here are some tried and true techniques to create your own tropical tomato paradise.
Before You Plant
Pick a sunny spot. Select a location that gets eight hours of sun exposure — even better if it has radiant heat from sunshine reflecting off of a wall. Tomatoes love heat!
Heat the soil. This step can be as simple as placing dark tarps or plastic over your vegetable garden. Raised beds will further increase soil heat.
Heat the air. Warm air is critical so keep the heat close. If you just have a few plants, you can fill wine bottles with water to create a wall around each plant. You can also buy commercial “Wall O’ Water.” Or think larger—from simple cloches using PE pipe to a wood framed “house” covered in 4-6 mil plastic sheeting. Voila — instant greenhouse! Water-filled gallon jugs placed inside will increase heat gains.
Ready, Set, Plant
Now you’re ready to start working the soil. Remove the tarp and work in composted steer manure, compost and any remaining cover crops. Feed the soil, not the plant. Next, apply mulch or a soil cover to eliminate weeds, keep the soil warm, and reduce water loss from evaporation. A commercial option is “Planters Paper.” It is water-permeable, discourages slugs and disintegrates over the season. Make slits in the cover to plant through. Add a natural calcium source to reduce chances of blossom-end rot. This disease shows up as a black circle spreading from the bottom of a tomato and often occurs when water fluctuations inhibit the plant’s ability to absorb calcium from the soil. Watering more regularly and adding additional calcium should help turn things around.
Invite the bees. Attract a variety of pollinating bees by opening cloches or other structures on warm days and placing flowering pots, such as lavender and marigold, just inside. Or try your skills at hand pollination by brushing each flower lightly with an inexpensive electric toothbrush with frayed bristles. This mimics the pollinating vibration (sonication) of bumble bees. Remove covers completely when nights are warm. Keep the water off. To minimize risk of late blight (Phytophthora infestans) and Verticillium wilt, select disease resistant plants and use soaker hoses to keep water from splashing soil onto leaves. Reapply your cover before late summer rains. Finally, keep the garden tidy—remove any infected leaves or plants as soon as possible.
Sit back and savor the abundance of delicious tomatoes from your own natural garden. The results are priceless and all your neighbors will be jealous!