Cold frames made of wood and double wall panels are a common sight in the home garden. An alternative made of stone proves to be more durable and stable. These instructions explain how to build a cold frame yourself from decorative plant stones.
How do I build a cold frame out of stone?
To build a cold frame out of stone, you need planting stones, filling material, string, wooden pegs, shovel, ruler and spirit level. Determine the area, place the stones along the marking, fill it and place the upper stones on top. Fill the bed in layers with manure and compost soil.
Material and tool list
To build a stone cold frame measuring 1.50 x 3.50 m, the following materials and tools are required:
- 28 plant stones (60 x 40 x 25 cm)
- Filling material, such as gravel, grit, earth or a mix thereof
- String and wooden stakes for staking
- Shovel
- Folding rule, spirit level
Choosing plant stones as a building material offers several advantages. Due to the hollow space, these stones have significantly less weight. The gap is also perfect as an additional planting area.
Construction instructions
Since a cold frame made of plant stones is lightweight compared to a mighty natural stone wall, you can do without a foundation. In a sunny, protected location, measure the base area and mark the route with strings. Then straighten the surface with the shovel. Proceed as follows:
- Place half of the stones next to each other along the marking as the lower level
- Line the interior of the bed with vole wire and a 5-10 cm thick layer of leaves
- Fill the planting stones on the first level with gravel or soil
- Place the remaining 14 stones on top at an offset
- Fill the planting stones on the upper level with compost soil
There are several options to choose from as a cover. A tunnel made of round rods and weatherproof greenhouse film is cheap and practical (€71.00 at Amazon). This has the advantage that you can replace the film with an insect net during the summer to use the cold frame as a raised bed.
Filling the stone cold frame correctly – this is how it works
One week before planting, fill the stone cold frame in layers with horse or cow manure and compost soil. First add the manure to a height of about 20 cm on the leaf layer. This is followed by a mix of garden soil, compost and horn shavings. The decomposition of the organic material creates growth-promoting heat, which allows the cold frame to be used from February/March to November/December.
Tip
A cold frame made of pallets is more mobile and much cheaper. Just 4 Euro pallets are enough to construct a suitable frame. Disused wooden windows with old leather straps as hinges act as a cover.
