As for balconies, small terrace gardens are essentially above-ground gardens, that is, gardens in pots. The various containers are arranged along the dwelling, on the periphery of the terrace or in the corners. Intended to preserve a certain intimacy or simply to brighten the terrace, they must nevertheless allow an easy circulation.
Which bins to choose?
Any container can be used to grow a terraced plant, as long as it is large enough – 40 cm in diameter is a minimum – and drainage is efficient. The choice of bins is essentially a matter of style. They are offered in various materials.
© Leroy Merlin
Wooden bins are of two types.
- Those in parboiled treated wood (pine or fir wood) have a rather rustic and coarse appearance. They have for them the advantage of the price.
- Others are a real work of artisan cooper. Cut in beech wood, more exceptionally oak, they are by far the most elegant.
In both cases, the great disadvantage of wood is its sensitivity to bad weather, especially moisture.
Terracotta containers are in the form of large jars or basins, usually round. Moisture does not bother them, it is the cold that causes them problems. However, terracotta pottery is less sensitive to low temperatures proper than to the expansion of the frozen wet earth that causes the pot to burst.
Various stews with hosta, fuchsia, heuchera, grasses – F. Marre
The natural stone bins are the exception, most being made of reconstituted stone (rock dust agglomerated by a hydraulic binder). They are very variable styles, rustic or avant-garde. Their advantage is their lifespan: they are almost eternal. Their disadvantage is their weight. Many exceed 100 kg. Their handling is then problematic. Conscious of their indignity, plastic containers often try to imitate the previous ones – less weight.
© Leroy Merlin
The plants in vat
Potted plants have the same needs as those in the ground. But if the roots of plants grown in the ground can develop at will, a plant containing it is limited in its explorations, both for water and nutrients. It is therefore a question of finding the right balance for the plants grown above ground: a tank large enough for the plants to find their account, not too big to prevent it from clogging the terrace.
Water the plants in tank
Watering of petunia – F. Marre
For watering, the principle is simple: it is necessary to bring the water when it is necessary, in the quantity which it is necessary, neither more nor less.
The implementation is however more delicate. Excess water causes root rot and compromises good plant growth.
At first, it is therefore important to ensure the evacuation of excess water, especially if the terrace is open to the four winds: a rain storm would quickly turn the tank into a small pool. Modulate the influx of water. Newly stocked plants require regular inputs, but in moderate amounts.
Plant shrubs in vats
The shape of pots important little, we can recover everything, near or far, reminiscent of a container: old bag, watering can pierced, box riddled, sink obsolete, wheelbarrow rickety … If necessary, we can adjust 2 or 3 boards and make your own wooden planter.
© Leroy Merlin
- Once the container is in place, line the bottom with a few inches of expanded clay ball or coarse gravel, or even pebbles or pebbles. Cover the drainage hole with a large shard so that it can perform its role for several years.
- Fill it with a good horticultural compost, possibly supplemented with garden soil to give it a more consistent texture.
- Before planting, immerse the container in water for a few minutes, then remove the plant. If the roots curl into a compact bun, scratch the root ball to get it right and improve the recovery. Open by hand or planting a planting hole barely larger than the root ball and position the plant. Bridging round the mound with potting soil and limit it energetically to anchor it securely.
- Water immediately, first once a week, then as the plants develop, more intermittently. Four weeks after planting, start organic fertilizer application.