agriculture Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to ...

and

gardening Gardening is the practice of growing and cultivating plants as part of horticulture. In gardens, ornamental plants are often grown for their flowers, foliage, or overall appearance; useful plants, such as root vegetables, leaf vegetables, fruits ...

, a cold frame is a

transparent Transparency, transparence or transparent most often refer to: * Transparency (optics), the physical property of allowing the transmission of light through a material They may also refer to: Literal uses * Transparency (photography), a still, ...

-roofed enclosure, built low to the ground, used to protect

plant Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...

s from adverse

weather Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloudy. On Earth, most weather phenomena occur in the lowest layer of the planet's atmosphere, the ...

, primarily excessive cold or wet. The transparent top admits

sunlight Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is scattered and filtered through Earth's atmosphere, and is obvious as daylight when t ...

and prevents heat escape via

convection Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convec ...

that would otherwise occur, particularly at night. Essentially, a cold frame functions as a miniature

greenhouse A greenhouse (also called a glasshouse, or, if with sufficient heating, a hothouse) is a structure with walls and roof made chiefly of Transparent ceramics, transparent material, such as glass, in which plants requiring regulated climatic condit ...

to extend the growing season. Historically, cold frames were built to be used in addition to a heated

. The name itself exemplifies the distinction between the warm greenhouse and the unheated cold frame. They were frequently built as part of the greenhouse's foundation brickwork along the southern wall (in northern latitudes). This allowed seeds to be germinated in the greenhouse and then easily moved to the attached cold frame to be "hardened-off" before final planting outside. Cold frames are similar to some enclosed hotbeds,merriam-webster.com
/ref> also called hotboxes. The difference is in the amount of heat generated inside. This is parallel to the way that some greenhouses are called "hothouses" to emphasize their higher temperature, achieved either by the solar effects alone or by auxiliary heating via a

heater Heating, ventilation, and air conditioning (HVAC) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality. HV ...

HVAC Heating, ventilation, and air conditioning (HVAC) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality. HV ...

system of some kind. Cold frames are found in home gardens and in

vegetable Vegetables are parts of plants that are consumed by humans or other animals as food. The original meaning is still commonly used and is applied to plants collectively to refer to all edible plant matter, including the flowers, fruits, stems, ...

farming. They create

microclimate A microclimate (or micro-climate) is a local set of atmospheric conditions that differ from those in the surrounding areas, often with a slight difference but sometimes with a substantial one. The term may refer to areas as small as a few squ ...

s that provide several

degree Degree may refer to: As a unit of measurement * Degree (angle), a unit of angle measurement ** Degree of geographical latitude ** Degree of geographical longitude * Degree symbol (°), a notation used in science, engineering, and mathematics ...

s of air and

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

temperature

insulation Insulation may refer to: Thermal * Thermal insulation, use of materials to reduce rates of heat transfer ** List of insulation materials ** Building insulation, thermal insulation added to buildings for comfort and energy efficiency *** Insulated ...

, and shelter from

wind Wind is the natural movement of air or other gases relative to a planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heating of land surfaces and lasting a few hou ...

. In cold-winter regions, these characteristics allow plants to be started earlier in the spring, and to survive longer into the

fall Autumn, also known as fall in American English and Canadian English, is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, in September (Northern Hemisphere) or March ( Southe ...

and winter. They are most often used for growing

seedling A seedling is a young sporophyte developing out of a plant embryo from a seed. Seedling development starts with germination of the seed. A typical young seedling consists of three main parts: the radicle (embryonic root), the hypocotyl (embry ...

s that are later

transplanted ''A.N.T. Farm'' is a Disney Channel original series that follows Chyna Parks (China Anne McClain) and her two best friends, Olive Doyle (Sierra McCormick) and Fletcher Quimby (Jake Short), who are in the "Advanced Natural Talents" (A.N.T.) program ...

into open ground, and can also be a permanent home to cold- hardy vegetables grown for autumn and winter

harvest Harvesting is the process of gathering a ripe crop from the fields. Reaping is the cutting of grain or pulse for harvest, typically using a scythe, sickle, or reaper. On smaller farms with minimal mechanization, harvesting is the most labor-i ...

Construction

Cold frame construction is a common home or

farm A farm (also called an agricultural holding) is an area of land that is devoted primarily to agricultural processes with the primary objective of producing food and other crops; it is the basic facility in food production. The name is used fo ...

building project, although kits and commercial systems are available. A traditional plan makes use of old glass windows: a wooden frame is built, about one to two feet tall, and the window placed on top. The roof is often sloped towards the winter sun to capture more light, and to improve runoff of water, and

hinge A hinge is a mechanical bearing that connects two solid objects, typically allowing only a limited angle of rotation between them. Two objects connected by an ideal hinge rotate relative to each other about a fixed axis of rotation: all other ...

d for easy access. Clear plastic, rigid or sheeting, can be used in place of glass. An electric heating cable, available for this purpose, can be placed in the soil to provide additional heat.

Uses

Cold frames can be used to extend the growing season for many food and ornamental crops, primarily by providing increased warmth in early spring. This means that it's possible to harvest vegetable crops ahead of their normal season when they are extremely expensive to buy. Some crops suitable for growing in a cold frame include lettuces, parsley, salad onions, spinach, radishes and turnips etc. One vegetable crop can occupy the whole of a cold frame or a combination of crops can be grown so that they mature in rotation in order to get a wide range of different vegetables throughout the year from a single cold frame.

Bulb frame

A "bulb frame" is a specialized kind of cold frame, designed for growing hardy or almost hardy

ornamental bulbous plant Ornamental bulbous plants, often called ornamental bulbs or just bulbs in gardening and horticulture, are herbaceous perennials grown for ornamental purposes, which have underground or near ground storage organs. Botanists distinguish betwe ...

s, particularly in climates with wet winters. Typically it is raised further above ground level than a normal cold frame, so that the plants can be seen better when in flower. They are often used for the cultivation of winter-growing bulbs which flower in the autumn or spring. The covers are used in winter to provide some protection from very bad weather, while allowing good ventilation. Then in the summer, the covers provide dry, warm conditions which many such bulbs need. Pp. 32–34

References

{{DEFAULTSORT:Cold Frame Greenhouses

Construction

Uses

Bulb frame

See also

References