Wednesday, October 12, 2011

Greenhouse Ground Bed Construction

There are many layout options when constructing a greenhouse. Many people prefer to have their plants individually potted and then placed either on the ground or on benches. Others opt for raised beds to plant in, while some decide to grow straight in the ground. Ground beds are useful for many purposes, but their main advantage is the ability to maximize greenhouse space. This is because ground beds offer more height for taller plants such as trees , whereas a raised bed will reduce possible growing height by the height of the bed. One of the major disadvantages of ground beds, however, is that they allow the roots of plants to grow through the garden soil into the native soil. This can be a large problem, especially if the native soil contains soil pathogens that are deadly to your plants. In addition, native soil is often more compacted and offers less nutrients.

Calculations:
I advise doing some planning instead of making inaccurate judgments. Decide on how big of a grow area you want, and estimate how much soil and how many edge-stones you will need. Keep in mind that the plants you will be growing may not like the dirt that your greenhouse is built on. Therefore, if growing trees be sure to clear out about 3-4+ feet deep of dirt to allow room for the deep growing roots. Annuals and most low-growing perennials should be fine with as little as 1-2 feet deep of soil.


Picking a soil:
There are many options when it comes to the soil that you will be cultivating in. It is important to pick one that is well draining and meant for garden use. These soils are usually have a higher sand content and less clay. Soils labeled "Garden Soil" would be ideal, but potting soil will work as well. Also, depending on what you plan on growing may affect your soil choice. For instance, when growing cactus, be sure to buy a cactus mix. So long as you are growing trees, shrubs, annuals, and most perennials, the typical garden soil should work just fine.


Digging and filling:
Again, keep in mind of what kinds of plants you will be growing in the ground bed and dig to an appropriate depth. Upon digging your bed, be sure to add a couple inches of gravel or rocks. This will provide drainage to the soil above. Some gardeners like to add a meshed material to place on top of the gravel layer. This helps preserve the drainage of your gravel by preventing soil from leeching. It is not required, but it will help in the long-run. Once your drainage layer is done, start filling the ditch with soil.

Finishing touches:
Place edge-stones around the perimeter of the ground bed to prevent soil dispersion and to define the grow space. You may also choose to fill soil all the way to the top of the edge-stones making a sort of raised bed.

Trouble-shooting ground beds:
If the soil has become compacted overtime it may inhibit the absorption of water and suffocate roots. To fix this problem you may add soil amendments which will recondition the soil and improve its quality. Alternatively you may till the soil using a shovel. This method involves the physical break up of the compacted soil returning it to a normal state.