Most of my summer vegetables are winding down now, the cooling temperatures serving as a cue that their mission has been nearly accomplished.

But if frost threatens before the last of my tomatoes have turned red, I'll drape a sheet of sheer fabric over their supporting cages to provide some warmth.

The white fabric sheets, sold as "row covers," can be used in two ways: floating, meaning they are draped over plants, or hooped, meaning they are attached to hoops inserted into the ground.

The latter method is more protective of fragile stems and foliage, as the hoops keep the fabric, however light, from crushing plant parts.

As colder weather sets in, row covers will likewise prove exceptionally effective at safeguarding cool-season vegetables, including spinach, radishes, cucumbers, potatoes, kale and lettuces.

The UV-protectant sheets cannot, of course, work miracles.

Nevertheless, they are capable of raising the temperature around plants by as much as 8 degrees F, which may prove to be the difference between life and death.

Row covers are obtainable in a range of dimensions and, should the need arise, can readily be trimmed to suit your requirements.

Furthermore, they are offered in three distinct weight grades.

Lightweight variants afford merely a couple of degrees of protection, and are therefore chiefly employed as insect barriers during spring.

They additionally permit approximately 90% of sunlight to penetrate to the plants.

Heavy fabrics afford the greatest warmth, yet they obstruct sunlight and water to a considerable degree.

Their employment likewise carries the risk of elevating the temperature excessively.

Medium-weight fabrics achieve a compromise by permitting 70% to 85% of sunlight to penetrate to the plants while elevating the ambient air temperature by 4-6 degrees F.

This may seem negligible, yet it can afford several additional weeks of growing time.

And brassicas that are protected by coverings (such as cabbages, broccoli and kale), along with leafy greens and root vegetables that survive the entire winter under cover, will hit the ground running come spring, long before their spring-planted counterparts acclimate.

Drape floating covers loosely over low-growing plants, securing them by burying their edges in the soil or by positioning stones or bricks along the perimeter.

Ensure that sufficient slack is provided to accommodate plant growth.

To safeguard taller or more delicate crops, purchase pre-formed hoops or fashion them yourself by bending pliable PVC piping into inverted U shapes and subsequently inserting each end into the soil to construct a frame.

Drape the fabric over it.

You will still need to secure the sheet’s edges to prevent it from being carried aloft by the wind.

Row covers may be deployed over an individual in-ground or potted plant, an entire row of crops, or a raised bed.

Even with protective measures in place, you will still be obliged to monitor your plants and prevailing weather conditions closely.

Periodically assess the soil's moisture levels to ensure that your plants are receiving an adequate supply of water.

Flowering plants that depend on pollination must be accessible to insects; therefore, monitor for open blossoms and time the removal of covers to align with their blooming periods.

Irrespective of the quantity applied, it is advisable to draw the covers back on warmer days so as to prevent your vegetables from being “cooked” prior to harvest.

Jessica Damiano pens weekly gardening columns for Reporters, in addition to which she publishes the Weekly Dirt Newsletter.

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