How to extend the growing season
Maybe winter will come but that doesn’t mean you should put those tools away just yet! Thanks to appropriate modifications, you will extend the growing season significantly after the first frost.
The following excerpt is from The Novel Organic Grower, 30th Anniversary Edition By Eliot Coleman. It has been adapted for utilize on the Internet.
Extension of the growing season: how to compete
We live in the era of supermarkets where customers have come to expect products that are out of season. The supermarket sells tomatoes in April and peas in October. To be able to compete, local growers should try to get closer to these goals during the time of year that their marketing operations are open.
For almost all vegetable crops, a longer growing season is desirable if it can be achieved economically. Vegetable growers can capture and maintain recent markets and obtain higher prices by making produce available as early or as behind schedule as possible compared to unprotected outdoor crops. A grower meeting local demand or running a market stand will find that the “everything, all the time” policy pays off greatly.
The secret of success
The secret to successfully extending the season without hitches or setbacks is to find the point where the extent of climate modification is in balance with the additional time, money and management skills needed to achieve it. When planning a longer season, remember that farmers need holidays during the year.
The murky days of December and January, which are the most complex months in cultivation, are probably worth spending for rest, reorganization and planning for the upcoming recent season. The goal of any season extension is always to keep systems as plain and economical as possible, without sacrificing the reliable control necessary to ensure the success of the protected crop.
A wide range of options are available. In this review, we will discuss most of them and then recommend those that are best suited for tiny vegetable farms.
Climate modification
When considering the possibilities of extending the growing season, we should be aware of other options than building a greenhouse or moving south. There are many low-cost or free practices that can make a significant difference in changing climatic conditions to the benefit of the grower. The general rule is that the more we want to modify the climate, the more energy we need to utilize to do so.
The easiest way to improve growing conditions for early crops is to find, create or improve such toasty and sheltered places.1 We can moderate the climate with minimal energy expenditure if we work with natural tendencies and try to amplify their effects.
Three common natural parameters that are logical candidates for modification are the degree and direction of slope; amount of exposure or wind protection; and the heat absorption potential of the soil (soil color).
Plastic mulch
The next logical step beyond coal dust is a plain sheet of material placed on the ground as mulch, which helps toasty the soil. The standard material is polyethylene plastic. Plastic strips, 1.2 to 1.8 meters wide and as long as possible, are laid on the ground with the edges buried to anchor them against the wind. Four things contribute to the popularity of plastics as commercial mulch.
Plastic mulch retains moisture, warms the soil, can prevent weed growth, and is easily mechanized for application and disposal.
Low covers
The next step beyond mulching is some type of low covering or structure over the plants. The advantage of these plain, low structures is their flexibility.
They can be moved or positioned to cover specific crops as needed. While the utilize of plastic mulch itself justifies its cost in the case of earlier crop maturity in the toasty season, in practice it is usually combined with a low plastic cover to obtain even better results.
This is a dynamically developing field, and recent products appear every year. I expect future changes will replace the design, but not the purpose, of these covers.
Crawler Tunnels
I mean “entrance tunnels”. unheated structures consisting of a single layer of plastic supported by spaced arches or hoops high enough to be walked and worked under. Structurally, they vary from very delicate units on the one hand to structures indistinguishable (except for the lack of additional heat) from a greenhouse. I have seen tunnels as long as 200 feet (60 meters), although 100 feet (30 meters) is a more common length and 50 feet (15 meters) may be easier to handle in climates that require special attention to ventilation.
Typically, the minimum width is 10 feet (3.7 meters) and the maximum is 17 feet (5.2 meters), although the most popular models range from 4.3 to 4.9 meters (4.3 to 4.9 meters) wide (enough to cover four 30-inch [75 centimeter] beds). In practice, width is a function of the materials used, the arrangement of plantings and vegetation in a variety of styles, from plain to sophisticated.
Greenhouses
The simplest greenhouse is just a stronger and slightly more complicated entrance tunnel. The main differences are what a greenhouse typically has greater structural stability and provides additional warmth. A greenhouse can be built from a 2×4 structure and will look very similar to the frame of a house. It can also be constructed using the same bent tube Quonset design as the entry tunnels, using thicker section pipes.
Additional heat energy for the greenhouse can be provided by burning any amount of fuel, but the most popular tiny greenhouse heaters and the ones I recommend burn natural gas or propane. They are equipped with a blower and are ventilated to the outside. Installation is relatively plain and the units can be moved with the greenhouse.
The purpose of the greenhouse
The purpose of a greenhouse is to create optimal climatic conditions for plant growth. The same should apply soil conditions. Plants grow intensively in the greenhouse, so special care should be taken when preparing the soil.
All the factors that were highlighted in the chapter on soil fertility are triple emphasized here. For greenhouse farming to be successful, the utilize of well-finished compost is required.
Heated greenhouse production of high-demand crops is a valuable magnet attracting customers to other farm products. It can also be a very lucrative area of specialization in its own right. But don’t go into this without thinking carefully about it first. Growing high-quality greenhouse vegetables requires real commitment to management and attention to detail.
Extending the growing season: how can it be done better?
A progressive breeder always has one eye on getting the job done and the other on how it can be done better. Today’s ideas were yesterday’s suggestions. The ideas of tomorrow will arise from today’s problems. The best recent concepts come from experienced practitioners and have been developed to respond to their needs.
Once you gain experience, More improvements for you as a tiny grower and countless other food producers are just around the corner.