Plants cultivated in raised beds generally need more water than if they were growing in a garden bed. Our five tips will show you how to make watering easier.
Casting (almost) without work - 5 simple ideas
Characteristic of a raised bed is its special layering of different organic materials, which slowly decompose and thus not only provide nutrients, but also a higher ambient temperature. Plants feel comfortable here, but they also need more water than in a conventional garden bed - after all, the moisture evaporates faster due to the heat. So that you don't have to lug watering can after watering can, we have put together these five tips to make your watering tasks easier.
The watering does not work here without work either, because at least the irrigation system has to be moved or, in the case of Ollas and other forms without electricity and water connection, refilled occasionally. You can also save a lot of water by following these tips:
- water as early as possible in the morning
- never past lunchtime
- prefer to water less frequently and more penetratingly
- than more frequently and with less water
If possible, connect the watering system for the raised bed to rainwater collection barrels, as this soft water, which has been warmed up from the start, is particularly suitable for watering the plants. Our tip 5 shows you how to do this.
Notice: It is sometimes advised to install sprinkler irrigation for raised bed plants. However, we advise against this, as watering from above wets the leaves and thus promotes fungal diseases. Furthermore, a lot of water is lost in the process and does not reach where it belongs: at the roots. Therefore, always water in such a way that the precious liquid gets directly onto and into the soil.
1. Watering by olla / clay pot
Ollas are a very simple but practical watering idea for raised beds. The word comes from Spanish and means "pot" - and that's what it is. Ollas are special unglazed clay pots with a lid that are dug into the ground and filled with water. Moisture slowly seeps out of the porous material straight to the roots, irrigating the surrounding plants as needed. The soil remains evenly moist but not wet. In addition, since the water remains in the soil, there is little loss through evaporation.
Choose a suitable pot when repotting.
You can buy Ollas in specialist shops or in Internet shops specializing in the garden. These pots come in different sizes and shapes. For a classic raised bed with a width of 130 centimeters and a length of 200 centimeters, you need two to three Ollas with a capacity of at least three liters each. Use these as follows:
- Dig the Ollas in the middle of the bed.
- They should be evenly spaced from each other
- and keep from the edge.
- The opening points out at the top.
- Fill the ollas with water.
- Put the lid on.
- Plant the plants all around.
In this case, you only need to refill the Ollas about once a week, or every three to four days in very hot and dry weather. Further watering is not necessary.
Tip: You can build Ollas yourself from two clay plant pots. To do this, close the drainage hole of one pot (e.g. with a piece of pottery shard glued from the inside) and glue the two pots at their respective opening edges with hot glue or silicone. Spread the material well so that the splice is waterproof. Now dig the home-made Olla in such a way that the bottom of the pot with the remaining drainage hole looks out of the bed. This is also used to fill the Olla.
2. Irrigation balls or cones
Irrigation works on a similar principle using so-called irrigation or thirst balls, which are made of glass or plastic. There are also irrigation cones, which are often made of clay. In contrast to the ollas, these balls or cones are not buried in the ground, but simply inserted with their pointed end directly to the plant roots. The water reservoir remains above ground.
The functional principle is similar to that of the Ollas: the water comes out as soon as the bed soil dries. It practically soaks up moisture until it is sufficiently saturated. This way the plants get exactly as much water as they need. Irrigation balls or cones save you the daily watering, but have a few disadvantages:
- the degree of evaporation is quite high
- it needs to be refilled more frequently
- You need quite a lot of them depending on the filling quantity
Most watering balls or cones available on the market are intended for indoor plants. These tend not to be suitable for raised beds unless you install a device for each individual plant. It is better to choose models with a larger capacity (e.g. Scheurich Copa XL with a capacity of 500 milliliters). You need about three to four of these in a small raised bed, for example for the balcony. Depending on the weather and outside temperature (as well as the thirst of the plants in the raised bed), you will need topping up every three to ten days.
3. Irrigation with PET bottles
Instead of buying the watering cones or balls for a lot of money, just get water or soda bottles with a capacity of at least one liter each. Glass or PET bottles are particularly suitable. It is important that the material is firm - soft plastic that gives way under pressure (or if there is a loss of pressure) is not suitable for this purpose. Seal the opening of the bottle with a suitable clay or plastic stopper (e.g. Blumat) and put the bottle upside down in the ground.
For a small balcony raised bed, you need three to four bottles so that you don't have to water them for a few days. For a normal raised bed measuring 130 x 200 centimetres, take six bottles, which you distribute evenly like the Ollas. Leave out the edge, but place the irrigation as centrally as possible with regular distances to each other and to the edges.
4. Drip hose or pearl hose
If you want to save yourself the regular refilling of Ollas or bottles, irrigation with drip or pearl hoses is also suitable for the raised bed. These are hoses that either have small openings at regular intervals (drip hoses) or are made of porous material (pearl hoses). Both supply the plants with water evenly and reliably without you having to do more than regularly turn on the tap. When using drip irrigation, the following points should be observed:
- Choose hoses that are as thin as possible for the raised bed.
- Use drip hoses with narrow drip spacing.
- It is best to lay hoses along row plantings.
- If the water connection is below the raised bed, a pump is required.
- Otherwise water connection at the same height
- or install above.
- Otherwise the pressure is not sufficient for watering.
For a raised bed measuring 130 x 200 centimetres, you will need:
- about twelve meters of drip or bead hose
- Connectors (T-pieces, connecting bends)
- Connection to the supply line
For the water supply, use either a tap or rainwater barrels. Water at least once a day for eight to ten minutes at a time.
Irrigation without electricity and water connection
Incidentally, drip irrigation also works without a water connection and electricity for the pump. For this purpose, you must install the water reservoir (e.g. sufficiently large rainwater barrels) above the raised bed so that the water runs through the hoses all by itself when you turn on the tap. With the so-called high tanks, a pump is not necessary. You can automate the system with solar panels that supply the necessary electricity. If you do not use elevated tanks, a pump could also be operated using solar power.