Extending the Growing Season

by Sandy Hollingsworth, Master Gardener

Mountain gardening means adjusting to a shorter growing season. Many people believe that there is little that grows above 7,500 feet. After some experimenting and consulting with those who have had more mountain experience, you will find that there are plenty of plants that will grow at higher elevations. Learning how to extend the season will make for even more success and diversity.

One method of extending the season is to start seeds indoors in February or March. A sunny window works, but tubular grow lights give the added benefit of more control and height adjustment as the seedlings grow. Seedlings may be transplanted to a cold frame and some seeds may be sown directly in the cold frame once you can get to it. Placing a cold frame near the house with a southern exposure and venting method will mean greater access and success until the outside temperatures are consistently above frost.

Using cloches when transplanting to the main garden will also help. These include Saylor Caps, Wall of Water, individual covers made of clear plastic or glass, and wire hoops which support fabric or clear plastic sheeting. Again, having a method for venting is important to regulate the temperature and humidity. Some mountain gardeners have had success adding old tires, black plastic or weed mat, at the base of plants to capture and retain heat in specific areas of the garden. Others use jugs of water to increase heat in an area. Additionally, wrapping the sides of your garden with clear plastic over a wire fence will both protect your plants from wind and capture heat in the ground. This can also have the added benefit of keeping hungry chipmunks and rabbits out of your garden.

Fortunately most of the above methods are inexpensive and won’t overheat cool weather crops. Whatever your chosen method, best wishes and welcome to the mountains.

If you have further questions, please contact the CSU Extension Office to speak with a Master Gardener or Extension Agent.