By extending the growing season, you can continue to have salad greens, beets, and carrots fresh from your garden. Low tunnels are an easy way to protect the cool season vegetables from freezing temperatures.

Produced by the Department of Communications at Kansas State University. For more information, visit our website at:

Low Tunnels Extend the Growing Season

The first thing to think about when you’re extending the season is to decide what kind of plants you want to cover. In front of me are some Bull’s Blood beets, which have a nice purple leaf and will develop some tasty beets as well, and some arugula. Other things that you might grow for extending your season into the later fall months would be lettuces, swiss chard, bok choy, and carrots.

The types of vegetables that I’m talking about are what we generally refer to as cool season vegetables, or vegetables that grow best when the daytime temperatures are cooler than 70 degrees.

There are some different methods for extending your season, and for the home gardener, probably the best method to use is some sort of row cover. A row cover might be what you know as the old sheet that your grandma used to put over her flowers to protect them from frost in the fall.

Other options would be what we call a low tunnel. That’s using a hoop of some sort to keep the fabric up off the plant, and to create a cushion of warm air over your plants to keep them from freezing. And, it helps to keep them growing when the weather gets cooler.

A simple way to make a low tunnel, or a low hoop house, is to get some simple pvc pipe, either bent pipe or bendable pipe, and just push it into the ground. If you’ve got a number of vegetables, you should have several hoops spaced out so that you’re supporting the row cover above the vegetables.

I do encourage everyone to find some bricks or something to weight down the fabric so that it doesn’t fly away when it gets windy. If it’s just going to dip down to 32 or 33 degrees overnight, you might take it off during the day if the daytime temperatures are still getting up into the 70s. Otherwise, the plants would get too hot under the row cover.

If your daytime temperature is staying in the 40s or low 50s, you should leave the row cover on, because it will help collect the heat under the row cover. And, it will help the plants grow more quickly – even in the cooler fall temperatures.

This feature story prepared with Rebecca McMahon, Kansas State University Research and Extension Horticulture Agent, Sedgwick County. For more information, visit your local county extension office or visit our website at

Horticulture Newsletter

KSU Horticulture Newsletter

Get more information from our weekly newsletter.

Find Your Local Office

Have questions or need help?

Local Extension Office Map

Click the map to find your Local Extension Office.

YouTube Videos

YouTube Videos

Watch K-State Research and Extension Videos.

Kansas Healthy Yards Tagline