Everywhere I go, people want to talk about our current drought in California. As I write this, it has been raining all day, but this is the first real rain we’ve seen in months and it’s February. Regardless of this rainfall, Northern California is still 50% under what is normal. Water conservation has become one of the first and main components of planning a new landscape and improving on an existing one. Here are some ways we can conserve water in the landscape:
1. Reduce the size of your lawn (or better yet, remove it)
I know, everyone loves their lawn. It is a great place for kids to play and fall on a soft surface. Many of us have fond memories of large, lush lawns from our childhood. But lawns require sprinkler irrigation, a broad spray system that uses a lot of water and is only necessary on turfs, like lawns, that have shallow roots running along the surface. Reducing your lawn area means you can cap much of your sprinklers and reduce that broad spray water output. Removing your lawns altogether is even better, but then what? (see #2)
Here are front yards where we reduced the lawn and added drought tolerant perennials and a patio:
2. Convert sprinklers to drip irrigation
Drip irrigation is very important in conserving water. Why is drip better than sprinklers? Because it is not broad spraying. It deeply waters just the roots of the plants and when combined with soil amending, which allows for quick water absorption, and mulching (see #4), it uses very little water while keeping the plants healthy. Can you just plant native plants and not water at all? No. We don’t get enough rain to sustain the plants without any watering. Is it better to just water with a hose? No, this is not efficient and uses more water than drip irrigation. With regards to lawns, can you just use drip irrigation on a lawn? Well, I haven’t seen that work very well. There was an irrigation design popular for a short time that involved lining the soil under the lawn with a zigzag of drip tubing and laying new sod on top of that. It was popular only for a short time because it wasn’t very effective for keeping the lawn looking evenly green and lush. So, what to plant instead of grass? (see #3)
Here’s what a drought tolerant planting area looks like with drip irrigation before we spread mulch over the soil. See how efficient the watering is? We use 6″ and 12″ emitting line off a 1/2″ solid feeding tube:
3. Plant drought tolerant plants
The plants that do very well here in the Bay Area, in addition to many CA natives, are plants native to Mediterranean climates, South Africa, Australia and New Zealand. Thinking about other like climates is more refined than just CA natives, many of which require more sun than much of our coastal areas get here. Alameda County has established a program and certification called “Bay Friendly” landscaping to identify this emphasis on drought tolerant, low maintenance plants and landscape design. These plants are labeled in many local nurseries Bay Friendly and may be a good choice for your drought tolerant planting plan. Remember that you can plant ground cover in the joints of flagstone paths and patios to get a turf-like feel in rethinking lawn-space (see path below).
Here’s some gardens where we removed the lawn and replaced with a drought tolerant landscape:
4. Amend the soil and spread mulch
Amending the soil is a fancy way to say break it up so water can absorb into it. When breaking it up, we “amend” with a dark soil, like compost, to revive our native clay soil. Clay soil is not bad, as many believe. It is difficult to work in and gets compacted if not amended or broken up. Have you ever seen someone’s sprinklers on and the water just runs off the surface and into the street? That’s because the soil is so compacted, the water has no way to penetrate it. That’s why it’s good to amend.
Mulch comes in a few varieties and choices. Most are some sort of wood cut up into different grades, either shredded or chipped. It is very important to retain the moisture of the soil and to hide the drip tubing. Have you ever seen a garden where there is no mulch and it looks very dry, maybe with tree roots exposed and a dull brown color to the soil, almost like sand? That dry, eroding soil needs a good soaking and a layer of mulch (about 3″) to come back to life. One detail to be careful of when spreading mulch is to keep it off the base of trees. It could cause fungus to grow because it doesn’t allow the wood of the tree to dry out which could lead to diseases in the tree.
Here’s a few examples of mulch types we often use, the first is fir bark minus, then shredded cedar and third is forest floor: