Greenhouses and greenhouses will significantly extend the growing season. It enables easy pre-growing of seedlings, protects plants against capricious weather, and is an investment for the future.
The greenhouse allows you to grow not only delicious and profitable greenhouse varieties of cucumbers, peppers or tomatoes, but also to pre-grow your own seedlings in optimal conditions and in more generous quantities than on the windowsill. And you can harvest leafy greens all winter long if they grew in the fall or very early spring, if you pre-planted them, or if they overwintered.
All these possibilities are offered by a regular, unheated greenhouse. It usually pays to invest in the most generous size you can afford. If you like to grow, it hardly happens that you would not use its area. In any case, the greenhouse should have a floor plan of at least 2.5 x 2 m, movement in a smaller one is quite difficult.
Where will it suit him?
There is a place for a greenhouse in almost every garden, thanks to variable sizes and shapes. However, think carefully about the location, it is a very prominent element of the garden. The place for him should be sunny. The least favorable is shading by a building or an evergreen tree. Partial shading by a deciduous tree is more acceptable. In spring, the bare branches let in enough light, but in full summer, the shading leaves don’t matter so much if the sun’s rays bypass it at least for part of the day.
However, full sunlight is ideal, when you compensate for any excess with blinds or white paint. However, it also depends on the material and its light transmission, see below.
The orientation of the greenhouse is also important. Along the wall facing south, plants will use maximum light and heat, which is especially advantageous in spring and autumn. In the summer, it is necessary to shade and ventilate even more. In the cold part of the year, the space inside is significantly cooled by the wind – if the shorter wall of the greenhouse is exposed to its prevailing direction, the temperature will drop more gently in it.
If you have a suitably oriented wall, a counter greenhouse adjacent to the wall is also an interesting solution. True, it lacks lighting from one side. The orientation of the wall is all the more important, definitely don’t build it on the north side of the house. This type saves space and disturbs the appearance of the garden less. And what is no less important – the wall accumulates heat during the day and radiates it at night, therefore the counter greenhouse cools down much more slowly. Unlike the free-standing ones, it is necessary to prepare concrete foundations for the counter one.
Why are polycarbonate greenhouses more common than real greenhouses today? Polycarbonate insulates better than glass – the thicker it is and the more cavities it contains, the better. If you plan to heat the greenhouse, polycarbonate is definitely a reasonable choice. Even for a tempered greenhouse, in which you will maintain a non-freezing temperature in the winter, it is more advantageous. But be careful, if you want to minimize heat loss, the construction also depends – plastic and wood insulate well, metal less well. Metal structures, on the other hand, offer longer durability and a generous choice of sizes and shapes if you have your greenhouse built to order. For galvanized steel, you can usually choose the color in advance, which the profiles will already be provided by the manufacturer. Wood is a relatively little-used, but beautiful-looking luxury. However, the protective coating needs to be renewed, especially for cheaper soft wood.
Polycarbonate disperses the sun’s rays better than glass, so the plants are not at risk of burns. But it emits a little less light and has a shorter shelf life.
A real greenhouse made of tempered glass (ordinary would be really dangerous to use) will decorate the garden rather than a polycarbonate tree. You can see into the greenhouse and out into the garden again, which is very pleasant. But the benefits are not just aesthetic. The glass transmits light more perfectly, which is a big advantage, especially for counter or partially shaded greenhouses. You will also appreciate full lighting when growing leafy vegetables early. They can handle the cold, but a lack of light leads to poorer growth and unnecessary accumulation of nitrates. Glass is also easier to clean than more delicate polycarbonate. And the summer rays can be moderated using blinds, mats or lime coating.
Internal and external blinds can provide shading, which prevent overheating more effectively. Internal ones, on the other hand, can serve as night insulation in the cold seasons of the year. Transparent glass is elegant and creates a feeling of airiness. However, it is true that it can become a deadly trap for birds. However, the solution is simple. UV stickers, almost invisible to the human eye, are bright blue to the bird’s eye. Just stick them on the outside. Or you can beautify the greenhouse with translucent glass paints. Any shapes warn of a fly-by, they don’t even have to be silhouettes of predators. The ideal distance between them is 10 cm, for a counter greenhouse, even more is sufficient.
Straight or sloping walls? Arch or tent?
If you intend to pre-grow seedlings, you will greatly appreciate the equipment in the form of shelves. They can only be installed on straight walls or the wall of a counter greenhouse. Handy are the foldable shelves that you can easily remove when you no longer need them and thus free up space for taller plants.
If you do not need this practical area, you can use the advantages of a greenhouse with sloping walls. They reflect less light and the plants get more of it. Especially if the slanted glazed area is facing south, it makes perfect use of the winter, as well as early spring or autumn lower sun rays.
In the summer, on the other hand, the sun shines more from above and rests on the even more curved tip of the greenhouse, which partly reflects it, so it is not so easy to overheat and burn the plants. Greenhouses made of shaped polycarbonate in the shape of a tunnel are able to use the light optimally throughout the day.
It might seem that the space under a sloping roof or an arch is unused and a flat roof would be more economical. But in addition to summer overheating, there would be a risk of winter snow accumulation. And thanks to higher shelves, hanging containers and a ladder or steps, you can use the space that you otherwise can’t reach.
A draft helps
It is usually unpleasant – for houseplants, people and animals. But in the greenhouse during the summer it is often a necessity. On hot days, it is necessary to let enough air into the greenhouse, it should change at least once an hour, but preferably more often and take away excessive humidity and heat. Ventilation windows are therefore necessary for all greenhouses, doors are not enough. You can ventilate most effectively through a skylight in combination with a door or a side window. Cool air comes in from the side and heated air rises up and out. Thanks to open windows, insects have access to the flowers of fruit vegetables (tomatoes, peppers, eggplants) and pollinate them. Automatic temperature-dependent window opening is practical – but make sure it is set well. It doesn’t always respond according to your wishes, and they can also change during the season.
Source: Receptář magazine