Year-Round Growing: Profitability and Tips
Well-functioning soil makes crops more resistant to freezing, and the soils themselves are better resistant to freezing due to the heat generated by soil life and the aggregation of the soil structure. This moderate reduction in soil temperature due to biological activity is crucial for successful off-season plant growth. Additionally, the common darkening of soil color as fertility develops is better able to capture solar heat than lighter colored soil. When soils function at this level, winter vegetable production becomes much easier. Growing winter vegetables on indigent soils is particularly tough.
Vegetables capable of saturating juices with additional sugar content significantly improve the taste with the onset of frost or frost. Crops that cannot do this simply die when temperatures reach the freezing point. Increasing the sugar content and improving the taste at the beginning of the frosty weather does not go unnoticed by the customer!
This is a time when vegetables grown in frosty climates may differ significantly from their counterparts from toasty regions. Carrots, cabbage, parsnips, leafy greens, Brussels sprouts, turnips, and rutabagas are a few well-known examples of cold-weather crops. It is generally true that the colder it is, the sweeter the vegetable, but above a certain frost threshold the plants will suffer.
This damage may be short-lived and may include water-soaked areas on the leaves that may develop after a frost. In vigorous crops, these areas recover quickly when temperatures rise above freezing, but at some point the damage can become indefinite. The temperature causing indefinite damage varies depending on the species and variety of crops, as well as the degree of plant viability. This is another reason why careful soil and environmental management, as well as seed breeding, are priorities for growers entering year-round production.
Planning the layout of a vegetable field for the winter season is even more significant than designing the field layout for the toasty season. During the frosty season, the sun moves in a low arc across the southern sky, which can cause shading difficulties that do not occur during the toasty season. The frosty season is also often a wetter season, which creates more challenges in soil water management. Due to the lack of leaves on trees and the loss of their wind-mitigating effect, frosty winds can also cause damage.
Beds prepared for the installation of a low tunnel. First the bags, then the hoops, then the covers. This photo is from when we were farming. Elementary, raised beds with exposed soil surface, mulched wheel tracks to keep weeds out and keep bags and covers from freezing to the ground. The field doesn’t look like that anymore.
Full south exposure and a south-facing slope can be especially useful in collecting sunlight during the frosty season. Fields located in this way are definitely the best places for year-round cultivation. Drainage management is crucial due to increased humidity during the frosty season, which is potentially harmful to crops.
Raised beds, properly spaced if on a slope, and the development of soil aggregates are indispensable to optimize drainage. Subsurface drainage in the field or ditches around the growing area may also be beneficial because groundwater levels can be high in winter.
The development of appropriate wind shelters, as described in Chapter 1, for cold-season crops is also of great importance.
Over the past few decades, recent types of construction have largely replaced glass greenhouses and frosty rooms. See-through polyethylene foil is often used to cover a greenhouse. Low tunnels covered with this covering largely replaced frosty frames.
Polypropylene fabric row covers have replaced woven straw rolls and mulch in the past. These contemporary materials are popular because they are very capable and are sold at a relatively low price. Unfortunately, they are relatively toxic to produce and dispose of, and plastic compounds can leach into soil and plants.
It appears that they are more likely to off-gass and leach when recent, and much less when they are older. This movement of plastic compounds into the growing environment does not appear to be excessive, and the functioning soil environment will likely decontaminate in due course, but a smaller amount is still probably best.
The advantages of polyethylene and polypropylene films are wide. When used properly, the materials can escalate solar heat gain, retain soil heat, and reduce or eliminate cooling winds. They also act as a barrier to excess moisture, thus creating a drier growing environment. Clear polyethylene sheeting is superior to polypropylene row covers in capturing solar heat, eliminating cooling winds and blocking moisture.
The row cover is excellent at retaining heat for protection at night and can be used without support hoops, often making field work easier. Depending on the desired conditions, the materials can be used sequentially or even in combination.