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Growing Tomatoes at 7,000 Feet

Sara McAllister
Sara McAllister waters her self-watering planters.

Gardening in the heart of the Rocky Mountains, just downriver from Aspen, has taught Sara McAllister a few things about extreme gardening. "The soil here is rocky clay and the temperatures can swing 40 degrees in a day," says Sara. But a difficult climate is not Sara's only challenge. As a garden center manager, she's always very busy in the spring helping other gardeners and finds it hard to get much time for her own garden. This has forced her to come up with some creative solutions—especially when it comes to growing tomatoes. "I wanted to try growing tomatoes here in Carbondale because everyone told me it was nearly impossible," she says. Sara quickly discovered that container gardening is the best way to get ripe tomatoes at 7,000 feet.

Growing Tomatoes in the Mountains

"For me, the Tomato Success Kits from Gardener's Supply are the only way to go," says Sara. The soil mix supports a great crop and she doesn't have to worry about the water reservoir running dry when she's working 10- to 12-hour days. Sara has also created her own customized planting strategy. "I crowd three to four tomato plants in each container," she says. Even though this means fewer fruit per plant, overall she gets higher production and an earlier harvest. Sara puts the containers on her sunny deck close to her awning windows. On chilly nights, she leaves the window open at night so the warm air from the house keeps the plants happy. Sara sells a different brand of self-watering container kits at her garden center, but she loves the tomato success kit from Gardener's Supply. "It's easy to assemble, not complicated to use and works really well," she says.

Sara has become so successful at growing tomatoes, that she's able to give many of them away. She gives some to a neighbor who loves to can them for her, and also trades tomatoes with one of her neighbors for bottles of wine. She even has extras to dry for the winter.

While Sara needs the containers to product tomatoes, She grows other vegetables, such as lettuce, cabbage, peas, and beans, in Grow Beds. "My Rocky Mountain soil is horrible," says Sara. "I fill up the Grow Beds with compost and lots of good soil. I find the black plastic sides help warm the soil earlier so the vegetables mature sooner," she adds.

Starting Seedlings

One way that Sara deals with the long Colorado winter is to start her own seedlings. She uses an APS seedstarter to start tomatoes, peppers, eggplant, herbs and other vegetables. "The capillary mat delivers just the right amount of water to the seedlings. I use a heating mat to keep the soil evenly warm," she says. She grows her seedlings in her living room under full-spectrum fluorescent lights. The result is healthy, stocky seedlings that are better than what's available at local nurseries. "I have people in the garden center that would prefer my APS-started seedlings over ones we buy from nurseries to sell," she says. Neighbors are such fans of Sara's seedlings that hey have nicknamed her "the germinator".

Once the seedlings are large enough, Sara moves them to her greenhouse, where they stay until they're ready for the weather outdoors.

Inspiring Others to Garden

Sara has been gardening for 14 years in this alpine environment. She believes that her success has inspired others to give it a try. "Most people think you can't garden here. Well, I've proved that you can," she boasts. "I have the best of both worlds; the beautiful Rocky Mountains and tomatoes to die for."

Last updated: 10/24/15