IRRIGATION FOR YOUR GARDEN
Originally featured on Garden Design.
Most plants need regular watering to survive, and even the most drought-tolerant ones will occasionally need a drink. Many factors play a role in determining how best to accommodate your garden’s water requirements.
Do you have a variety of water needs?
Drought-tolerant plants, lawn areas, perennial beds and edible gardens all require varying amounts of water and frequency. When planning your yard or garden areas, think ahead about how much water individual plants need and group plants together that are similar. This will make watering easier to manage (and save water) when all the plants in one area get the same amount of water and at the same frequency. It also helps to keep neighbouring plants healthy by not overwatering dry-loving plants or underwatering water-loving plants, simply because they are located next to each other. Also, keep in mind that the shallow roots of annuals will need more frequent watering than deep-rooted perennials.
What is your climate like?
Different environments not only for different amounts of water, but different methods of application as well. When it comes to climate, simply making sensible plant choices is one of the best things you can do for your garden – trying to grow tropical plants in the desert will only cause yourself, and your plants, a lot of stress.
What is your average rainfall?
Adjustments for rainfall can happen daily, weekly, monthly or seasonally. If you’re lucky enough to live in an area where Mother Nature takes care of some of the watering for you, make sure you have a watering system that lets you adjust accordingly.
Is your site flat or sloped?
Application methods and rate will be different for water that is going to stay put on a flat surface and soak in or if it’s going to run down a slope. Figuring out the correct watering schedule and amounts for flat ground can be difficult enough with differences in water needs, soil types or exposure; but watering on slopes adds another layer of complexity. Considerations need to be made to compensate for gravity, trajectory angles and pressure differences due to elevation changes. Check valves should also be installed on lower levels to keep residual water from leaking out.
Does your garden get a lot of sun or is it shaded?
Evaporation from bright sun can steal precious water in a sunny garden by as much as 50%. Shaded areas hang on to moisture longer and may become waterlogged. Define the different areas, or zones, of your entire yard or garden. Areas that receive full sun would probably do better with drip or soaker-type irrigation that protects against evaporation, as would areas that are prone to wind. Zones that are constantly shaded should be on a different schedule than those in sun, as they will soon become overwatered compared to the hotter, drier areas.
What is your soil composition?
Sandy, clay, rich, rocky — all play a part in how well water is absorbed and eventually drained from an area.
- Clay soil is often referred to as heavy. Water is absorbed slowly and spreads out, and clay can hold a lot of it. It’s best to water clay soils at a slow rate to allow it to soak in. Clay soil is prone to cracking when it dries out and roots can have a hard time penetrating it. The best amendments for clay soil are compost or organic matter to improve drainage.
- Sandy soil allows water to soak straight down without holding onto much of it. Plants will need to be watered more often and in a wider arc to get roots to spread. The best amendments are compost or organic matter to help hold in the moisture.
- Loam soil is a combination of sand, silt and clay and the best for plant growth. Loam is rich with nutrients and distributes water evenly with good drainage.
Most gardeners will have a combination of answers to the above questions — you may have some areas in sun and some in shade; a mixture of level surfaces as well as slopes; or some areas may get more wind than others. A good understanding of all of these factors will help you make the best choices in matching the right garden watering system — or combination of systems — to the individual needs and areas in your garden.
Depending on your answers to the above, choosing the proper irrigation method can be confusing. Here’s an overview of the most common options: