The effects of climate change here in Marin have never been so obvious. Cali- fornia has declared a state of emergency and the drought in Marin is the worst since 1977, with the potential to become the worst in recorded history. Already, farmers are scaling back their crops or skipping the season altogether, and ranchers are making plans to truck in water and upgrade their collection systems. In Inverness, for example, only 15 inches of rain have fallen this winter, compared to an average of 37.5 inches, making this the driest year on record. The need to build resilient communities and farms has become more important than ever.
So what can the majority of us do on a small scale, around our own homes and gardens as we head into the summer? As a permaculture-based garden designer in Marin, thinking about ways to conserve water in landscapes is a priority. My top water conservation strategies and tips that anyone can use in the garden immediately are mulching, hügelkultur and the use of greywater. It would also be wise to plan ahead now for the rainy season by setting up rainwater catchment. If your garden is on a slope, this is a good time to think about terracing your hill with a system of swales and berms in order to help your soil more effectively hold and store rainwater in the future. Permaculture draws from in- novative and ancient water conservation methods that are being practiced all over the globe; most of these methods provide additional benefits like soil conservation and improvement, enhanced biodiversity and increased yields. In my own garden, the following water conservation strate- gies are making a noticeable difference. They also have the added benefit of being inexpensive, simple and earth-friendly.
Mulching is one of the simplest and most effective ways to conserve water in your garden, whether or not you are using a greywater system. Using natural materials such as straw, leaves, wood chips, cardboard and newspaper as mulch helps hold in moisture and conserves water. As the mulch decomposes it becomes an excellent source of food for the bacteria and organisms living in the soil, enhancing the soil quality and feeding plants. Mulch deters weed growth and, when used over time, revitalizes soil and promotes better plant growth. Living mulches are excellent too, especially if they double- or triple-stack functions such as fixing nitrogen in your soil, attracting beneficial insects, repelling pests or providing food (think strawberries)! In my own little microclimate, I like to use clover, chickweed, sweet alyssum, poppies, strawberries and many different herbs. There are many excellent living mulch or groundcover plants available. Look for drought-tolerant species suited to your particular microclimate and sun exposure.
Another way to conserve rainwater naturally on a hillside garden is by sim- ple terracing with swales and berms. I did this on my own hillside fruit orchard last winter with a combination of hand-dug swales and inexpensive straw bales acting as the berm along the contour of my slope. The straw bales stack multiple functions: as raised beds in the first season for planting annuals, and later, as the bales decompose, as a way to hold water and nutrients in place and as a natural source of composted food for my fruit trees. I like to use rice straw for mulch- ing and terracing, as it contains very little weed seeds and breaks down quickly. An- other excellent way to create low-cost, effective swales on a hillside is known as “hügelkultur.” This refers to laying down logs and other natural wood debris, and then covering it with soil into which plants and trees can be planted. As the logs decompose, they provide nutrients to the organisms living in the soil; they also act as a sponge, soaking up water during rainfall and releasing it into the soil as needed. Hügelkultur-style plant- ings do not need watering, even in dry climates and during droughts. I have experimented with this in an area of my own hillside orchard, using logs from a fallen oak tree buried under a few inches of soil to create a swale around my thirsty citrus tree. Then, I spread used straw from the chicken coop, rich in nitrogen from droppings, as a natural mulch and fertilizer. The combination of straw bale terracing, swales and hügelkultur tech- niques has made a huge difference to my garden’s water use this year. I have not (yet) needed to water my orchard, and all the fruit trees are thriving.
To learn more practical water con- servation strategies for your own home and garden, please join the West Marin Climate Action for a free webinar on Thursday, June 24 at 7 p.m. A panel of experts will lead the conversation, in- cluding Marin County Supervisor Dennis Rodoni, expert gardeners, a greywater/ rainwater catchment specialist and many others. For full details and to register, please visit westmarinclimateaction.org.
Jhaya Warmington splits her time between Fairfax and Bolinas.