13. The Native Meadow Experiment - Plants
The next step in replacing my backyard lawn with a native meadow is to create a precise planting design and plan the installation. (See this earlier posting to read about the first few steps of this experiment.)
My goal is to re-create a grassy meadow resembling what would have been in this area prior to human impacts. In terms of plant communities, it is likely that where I live along the eastern edge of the San Francisco Bay was a Coastal Prairie plant community. The plants of the Coastal Prairie are primarily grasses, some small shrubs and numerous wildflowers. It amounts to a pretty long list of fun choices, including things like Purple Needle Grass, Sky Lupine, Pacific Coast Iris, and California Poppies.
Plant Selection and Layout
Narrowing down the choices involves considering the site specific environment as well as personal aesthetic preferences. Since the starting point is a list of plants native to this area, many things are already working for us – for example all of the plants are used to the local weather patterns and shouldn't need a lot of extra water once established. The basic site factors are: exposure (full sun to part shade in my case), soil type (amended clay), water use (drought tolerant). Disease and pest resistance is also important – native plants naturally resist the native pests, but there are plenty of non-native ones out there, and some plants are more susceptible than others. Other important site factors that may come into play elsewhere are deer resistance and fire resistance, but they’re not a concern in my small fenced backyard.
Aesthetically, you want to consider the mature size of the plants, what time of year they flower, and when they are dormant. The arrangement should try to provide enough variety so that something is looking good year round; other than that things can vary quite a bit according to personal preference. Since this is an experiment for me to study native plants, I've decided not to go with a straight “restoration” approach where the design resembles a rectangle of wild prairie cut out of nature. I want to have more variety so I can watch and learn about how the different plants grow.
Also, I can’t resist expressing my interest in geometric patterns in the layout of the plants. I've already got a Golden Section rectangle as a frame, and am going to express the inscribed spiral as a stone pathway. To work within that, I've decided to plant the grasses in widely spaced rows, leaving space for the other shrubs and wildflowers to fill in.
Irrigation
Even though we are using native plants that don’t usually require irrigation after they are established, you will still need to water them for the first 1 or 2 dry seasons. It is also possible that during big heat waves or extended dry periods some plants will need extra water to stay healthy. Depending on the size of the area and your available time and money, the options vary from hand watering to a fully automatic drip irrigation system. In the case of my small backyard, hand watering will be easy to do, so I won’t install an automatic system. However, I did consider where I would place a sprinkler and hose to be sure not to block the good spots.
Planning the Planting
The plants I’m using can be divided into three rough categories: grasses, year round shrubs, and seasonal perennials/annuals. The focus here is the grasses because they will be planted first. This is for two reasons: they are cool season grasses which start their growth spurt in the early winter, and they also need to get a head start to become well established before there is too much competition.
Remember that one of the biggest challenges in establishing a native grass and wildflower meadow is weeds. In addition to sheet mulching, you want to time the planting to maximize conditions for establishment. For a plant to get established, it needs time to adapt to its new environment, grow its roots into the new soil and ramp up its growth processes. During this time they need extra water and regular removal of weeds that will compete for sunlight, water and nutrients. If the plant is put in the ground at the beginning of its primary growth period it can usually become established in 12 to 18 months. So getting the grasses in early allows them to get going before the spring weeds come up and get as much growth time as possible before late summer dormancy.
Another big decision is whether to use seed or pre-grown plants. In my case, because it is a small area and there is definitely a lot of weed seed in the ground, I’m using nursery grown plants from containers. This can get expensive in larger areas, but the battle with the weeds will be harder if you use seed.
In the late spring, I may add in some other shrubs and ground covers, but any annual wildflowers should wait until after the grasses are established – at least one year. As you can guess, an annual plant that completes its life cycle in one season is going to grow faster than a plant that has a multi-year life cycle. Therefore the other plants need to be well on their way before you introduce the fast growing wildflowers.
Finding the Plants
Your plant selection is also dependent on what plants can be found at local nurseries in enough quantity to fill up the space. When dealing with native plants, and especially seasonally dormant grasses, this can be a bigger issue than you might think. People tend to buy plants that look healthy and are flowering, so a nursery isn’t going to keep a large inventory of a plant when it is dormant. Native plants can also be harder to find than non-natives at the typical nursery. See my Resources page for more information on native plant nurseries.
When to Plant
Generally you want to plant California natives in the late fall, the exact timing of the planting depends on the amount of rain and the temperatures. Ideally you get them in the ground after a little bit of rain, but before things are completely saturated, and before the days get extremely short, or particularly cold. This year we had a lot of early rain and the soil got quite saturated before I could get things ready, so now I’m waiting for a dry spell before getting started. I’m loving all the rain, but hoping for a week or two of dry weather soon!
References:
Designing California Native Gardens, by Glenn Keator and Alrie Middlebrook
Handouts and Notes from my attendance at the California Native Grass Association’s workshop: Using California Native Grasses in the Water-Conserving Landscape www.cnga.org
Creating a California Native Meadow by David Amme, as published in Grasslands, A publication of the California Native Grass Association.