Cold Frames - Mini Greenhouses for New Seedlings

Notes From the Gardener

Richard Reading The Seed Catalogue
Richard Reading The Seed Catalogue


In this climate of ours where winters linger and springs are short, many gardeners employ cold frames to get a jump on the growing season. Cold frames are mini-greenhouses used to start new seedlings, or protect them from the cold of early spring. In fact, they are sometimes called "poor man's greenhouse" because they are cheap and simply constructed.

A cold frame can be something as simple as a wooden box with a sheet of glass placed over it, but most are constructed of four boards nailed together into a rectangle. To maximize the exposure to the sun, cold frames should be located in a southern exposure, preferably on a slope. Covers can be made of glass or plastic, but must shut tightly to protect young plants from freezing temperatures. Depending on the severity of the cold additional covering might be necessary, such as blankets, tar paper or pine needles.

Cold Frames

If you really want to get a jump on the season you can add a heat source to the cold frame. Here are three suggestions:

1.You can build your cold frame next to your house, adjacent to a cellar window. On very cold nights all that will be necessary to do is open the cellar window to allow heat from the house into the covered cold frame.

2.You can also deliver heat to a cold frame by stringing incandescent light bulbs into the interior. The number of bulbs you use and their wattage depends on the size of the cold frame. I have used 40 watt bulbs and found them sufficient.

3.Another method I have had success with, but requires more labor, is using the natural heat given off by composting manure. First, dig a pit 18" deep where the cold frame is to be located. Then fill this with moistened, fresh stable manure if available. After a few days turn the manure, moisten it if necessary, and cover with a few inches of soil. Locate the cold frame over the compost and heat from below will keep the soil and plants warm.

Cold frames must be watched carefully for cold is not the only danger. On a sunny day the heat in a closed cold frame can shrivel up tender seedlings in a very short time. So you must be prepared to remove or prop open cold frame covers on a sunny day and even provide shade using netting or cheesecloth if necessary.


Applying Mulch, Mowers and Moisture

Notes From the Gardener



All that back breaking work of Spring has ended. the seeds have been sown, the plants are in, the carrots have been thinned and the tomato stakes are in place. There seems little left to do but sit back and watch summer take the crops to fruition. Aahh, Summer. That great deceiver that uses its charms to lure you away from the garden and gives you the illusion that there is little to be done but wait for the plants to produce fruit.

Yes, Summer is boating and swimming, camping and cookouts. Summer is also hot and dry, full of insects, and the season of the weed. Without the gardener to stand sentry, summer can steal a garden away. Summer presents the gardener with many formidable opponents, such as insects, weeds, and extremes of heat and drought.

Extended periods of drought and high temperatures like we are currently suffering, turn gardens and landscapes from green to brown. Although we have no control over rainfall, we can, however, increase the soil's ability to retain the moisture it receives.

A soil's ability to retain moisture is primarily determined by the soil particle size. Soils made up of large particles (sand) do not hold moisture well. Clay and silt soils hold moisture well, but once dried they become dense and take up moisture slowly.

Adding large amounts of organic matter (humus) to the soil will increase the soil's capacity to take up and retain moisture despite the original make up of the soil. Humus will help heavy soils to take up moisture more readily and will help sandy soils to retain water.

The second most important - MULCH! At the end of the Spring when the soil has heated up and the rains have come to an end - that's the best time to mulch. It helps conserve the moisture in the soil and it prevents the weeds from growing.

Timing is of importance in applying mulch. You don't want to do it too early, because then you'll prevent the soil from warming up. You don't want to do it too late because a lot of the moisture will have already escaped and you'll be looking at a long dry period (like this summer).

You can recuperate an overly dry growing bed by watering it well, and then mulching heavily to prevent loss of further moisture to offset a long dry season. Even with water restrictions in place (we've been hauling a lot of water by hand this summer), you can do a small area of the garden each evening (and evening is the best time to water effectively).

As far as materials for mulch, you can use most anything. I like to use anything organic, such as leaves, gathered the previous fall and left in a corner pile to decompose as much as they can before I put them on. I find leaves and old hay that I get from local farmers to be the very best. Those of you with grass catchers on your mowers can spread the clippings thinly right on the garden beds.

And for goodness sake, don't be worried about introducing weed seed into the garden! Few will sprout from under a mulch and those that do can be easily pulled out and left there to become part of the mulch itself.

Hot and dry are by far our worst enemy this year. Safeguard your garden by mulching and you'll still harvest a good crop.