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Growing Under Cover

The Master Gardener’s Bookshelf

Growing Under Cover: Techniques for a More Productive, Weather-Resistant, Pest-Free Vegetable Garden by Niki Jabbour

Review by Susan Wilhelm, Extension Master Gardener

Growing under cover book image - front

All vegetable gardeners deal with pests. Fortunately, there are cultural and preventative controls to discourage pests, such as planting flowers to attract beneficial insects. Growing Under Cover: Techniques for a More Productive, Weather-Resistant, Pest-Free Vegetable Garden by Niki Jabbour is a guide to another tool—physical barriers or garden covers, including row covers, mini hoop tunnels, and cold frames that protect plants from insects, deer, rabbits, and birds.

Jabbour starts by explaining that pest control is only one of the purposes for what she calls “undercover gardening.” Other purposes include extending the growing season, summer shading, and protecting plants from extreme weather. She says undercover gardening is easier than one might think and that garden covers work in small spaces (raised beds and balconies) as well as larger gardens. For example, container gardeners can extend the growing season by using a tomato cage covered with polyethylene to protect plants from late or early frosts.

The first step in determining the appropriate garden cover is deciding the gardener’s goals. For pest deterrence, Jabbour suggests insect barrier fabric in combination with crop rotation to protect plants from pests such as cabbage worms, squash bugs, flea beetles, and Colorado potato beetles.  Fabric row covers and mini hoop tunnels also work. She notes that crop rotation, combined with physical barriers, helps prevent pests that overwinter in the soil, such as flea beetles and Colorado potato beetles, from getting trapped under a row cover if susceptible vegetables are planted in the same place over several years.

Jabbour suggests starting out small, trying row covers or mini hoop tunnels that are easy to make and relatively inexpensive. For example, mini hoop tunnels are hoops made from 9-gauge wire, PVC pipe, metal conduit, or half a hula hoop covered with a fabric such as an insect barrier or light-weight row cover fabric made from spun-bonded translucent polypropylene. Both allow light, air, and water to reach the plants while serving as pest barriers.

Bed with row-cover hoops at the MGNV Organic Vegetable Garden
Photo © Judy Salveson
Row cover over hoops in a raised bed protects eggplants from flea beetles early in the season.
Row cover over hoops in a raised bed protects eggplants from flea beetles early in the season at the MGNV Organic Vegetable Garden .
Photo © Bob Johnson
Self-pollinating cucumbers growing under row cover in a raised bed.
Self-pollinating cucumbers growing under row cover in a raised bed. at the MGNV Organic Vegetable Garden
Photo © Bob Johnson

Other garden covers include cold frames and, for those with larger spaces, polytunnels and greenhouses. Jabbour addresses each, covering everything from site and materials selection to ventilation and watering. She also discusses strategies for identifying and dealing with diseases and pests, such as early blight on tomatoes or aphids.

Growing under cover book image - backfront

Growing Under Cover also contains a detailed growing guide for a variety of vegetables. For each vegetable, Jabbour provides general planting, growing, and harvesting information with appropriate cover strategies. For example, when growing arugula, cover strategies include insect barriers to prevent flea beetle damage, shade cloths to delay bolting, and row covers, mini-hoop tunnels, and cold frames to extend the growing season. Similarly, insect barriers can prevent leaf miners from laying eggs on beet leaves and Swiss chard. In both cases, it is important to weigh down or bury the fabric’s edges to prevent insects from sneaking under the cover.

For the vegetable gardener interested in trying garden covers but not sure how to use them, Gardening Under Cover is a good place to start. Great photos, helpful tips, such as how to choose the correct sized row cover, and clear instructions throughout make it easy to use. While Jabbour gardens in Halifax, Novia Scotia, Canada, her techniques work readily across garden zones.

Growing Under Cover (Storey Publishing, 2020) is available at the Arlington Public Library, the Fairfax County Public Library, and national booksellers.

Interested in learning more about garden covers? Check out these resources: