Drip Irrigation: Easy-Going Plant Watering

Water is an incredibly important resource and is urgently needed for the lush growth of both ornamental and useful plants. However, it's not absolutely necessary to use expensive drinking water. On the contrary: distributing collected rainwater via drip irrigation is significantly more efficient than conventional watering methods. What's more, it proves to be extremely practical!

As the name suggests, drip irrigation waters plants droplet by droplet using specially perforated hoses. This irrigation system offers many advantages:

• It's incredibly efficient because water is delivered directly where it's needed—at the plant's roots.
• Since there's no overhead watering, damage to plants from sunburn or fungal infections is minimized.
• It eliminates the need for lugging heavy watering cans.
• It's easy to control and can automatically water plants even during extended absences (e.g., while you're on vacation).
• Drip irrigation can be used on all types of terrain, including slopes.

There are two different types of drip irrigation: above-ground and underground installation. The latter is also called subsurface irrigation. The basic setup for both systems is quite similar. In principle, the drip hoses offered for subsurface irrigation can also be laid above ground. Generally, the hoses are laid out in a grid pattern. Irrigation systems that rely solely on gravity and thus don't require a pump (i.e., no power connection) are particularly advantageous for small gardens and allotments.

The drip hoses should have internal, pressure-compensating drip emitters every 30 to 50 cm (about 12-20 inches). This ensures a consistent water output for laying lengths up to 400 m (approx. 1300 feet). For subsurface irrigation, the drip emitters must also meet specific requirements. These include a high pressure compensation range and mechanisms to protect against leakage, clogging, and root intrusion. Furthermore, they need to be self-cleaning.

One of the most crucial components is the filter system. It must be adapted to local conditions. Depending on the water quality, simple disc filters, sand separators, or gravel filters can be used. The filter system is fundamental for trouble-free operation.

The system also requires a pressure reducer. The irrigation system connects the inflow area to the end of the drip lines. To prevent a vacuum situation, a ventilation valve is needed. For automating drip irrigation, a good selection of solenoid valves, timers, and control units are available commercially. These can often be combined with other practical aids, such as soil moisture meters. The entire system can be perfected with suitable fertilizer dosing units, which allow liquid fertilizer to be fed into the system at any time.

The drip hoses are laid either on or in the ground, similar to underfloor heating. For subsurface irrigation, the laying depth is typically around 5 to 10 cm (2-4 inches), depending on the soil and plant type. To ensure uniform moistening of the entire area, drip spacing of 30x30 cm (12x12 inches) or 50x50 cm (20x20 inches) has proven effective in practice.

If you're creating a new garden, subsurface irrigation is a great option. For existing beds, the drip hoses can simply be laid on the ground. The hoses aren't very noticeable, as they usually have an earth-brown color. Above-ground installation offers the advantages of being able to check the functionality of the drippers at any time and easily reposition the hoses.

Once the system is set up and running, it saves many steps and ensures optimal water supply for all plants using a fraction of the previously needed water. With drip irrigation, your garden's total water consumption can be reduced by 30 to 50 percent.