When you peel off a layer of turf grass, the soil beneath is often compacted, depleted of nutrients and life, and polluted with salts and other chemicals. These chemicals may have accumulated from ongoing applications of fertilizers and pesticides. Or possibly, poor irrigation practices – short, frequent watering periods – that leave behind salts found in our water, especially here in Southern California. Healthy soil, in contrast, is full of life – microbial organisms, insects, and other animals. This blog post is about how one can one change a boring, green desert called lawn into a vivacious, biodiverse Southern California ecosystem supported by dynamic, living soil.
Wildflowers for a healthy garden
Many gardeners view bare dirt as an artist’s canvas. If it is compacted and depleted, they may till or turn it, amend it, and build it. They pull or poison weeds, and then they design and color it with new plants and paths.
To me, however, gardening is a kinder, more gentle activity. Every action one takes in the garden is a form of disturbance, even destruction. In fact, I must confess, each time I take a shovel to the soil I apologize for any damage done. Insects, microorganisms, worms and more are trying to make a living below, and so I whisper, I am sorry if I am disturbing you. And this is why annual wildflowers are so important to me as a gardener.
I try to guide the land towards health by taking clues from nature. Amazing wildflower displays often occur in natural areas following violent disturbances such as fires or floods. These annuals burst into bloom reminding us that life includes loss, and loss is often followed by the greatest gifts. Wildflower seeds may have lain dormant for years, awaiting a catastrophic event, and then it is their turn to shine. The lost trees and shrubs will return in time, but the nearly instantaneous growth of wildflowers prepares the soil for them.
A newly turf-liberated area can burst into exuberant bloom, similar to naturally disturbed lands. Unlike natural land, the newly exposed garden soil has few seeds, and probably those are mostly noxious weeds. As a gentle gardener, I provide the seeds that should have been there. I wish that I had a supply of seeds from the wildflowers that graced our land before Europeans burst on the scene, but I have to make do with what I can get.
I have found that my garden responds in a manner similar to what I observe in nature. The best wildflower displays occur during the second and third years after I free the garden from the lawn. Gradually, as the perennial shrubs and trees become established insects, lizards and birds take up residence in the garden, and the wildflowers take a back seat. Still, wildflowers put on an amazing display each spring, and I look forward to wonderful colors both at home and in the wild.
Plan and acquire seed
The first step to a beautiful wildflower display is planning. Decide which wildflowers you want and whether you want them mixed, in drifts, or in small patches. After the first year, the wildflowers themselves will help you decide who and where they will be.
Be sure to purchase seeds from reputable growers (eg. Theodore Payne Foundation, S&S Seeds, Larner Seeds, Seed Hunt) who specialize in California natives. If possible, use locally-native wildflower seeds, but note that it is illegal and unethical to harvest seeds from public lands without a permit. Wildflowers have been in decline for many years, leave the seeds in place.
Seed mixes from trust-worthy sources include native annuals that are adapted to similar conditions, such as dry shade, coast, or mountain mix. In addition, they are free of seeds from nonnative, invasive species.
As a rough guideline, one ounce of seed will cover approximately 140 square feet (14’ x 10’), though this depends on seed size, percentage of viable seed, and how much chaff is in the mix. In fact, I have found seed coverage numbers on the web that vary from one ounce of seed per 100 square feet to 1,000 square feet! Nonetheless, S&S Seed, and Tree of Life Nursery give an estimate of one ounce for 136 square feet. If you use too much seed, you will both waste money, and are likely to have a less showy display. The crowded seedlings will compete for nutrients and sun and may not develop into large, showy adults.
Weeds can be a major impediment to a successful wildflower garden, therefore it is important to remove as many as possible before seeding. If you have peeled back the lawn, then you have gotten rid of many weeds, however, weed seed and pieces of weedy grass that can grow new roots and leaves are likely to be present below the surface. Since it is easier to remove weeds from an empty bed than to try to work around wildflower seedlings, you may want to water newly exposed garden beds to encourage weed growth and removal before you sow the seeds.
Once you are ready to sow the seeds, lightly rough up the surface with a rake. Do not cultivate the soil deeply. This is unnecessary and counterproductive as it creates more soil disturbance and brings up additional weed seeds. If the soil is covered with leaves or mulch, clear the surface, sprinkle the seeds and replace a light layer of mulch, no more than about two to three inches. Avoid coarse wood chip mulch that will bury the seeds. A thin layer of medium-sized pebbles or sand can also provide a good surface for seeds to germinate on. Roughing the surface and lightly covering it with mulch provides nooks and crannies for better contact between the seed and soil, and it keeps the seeds from drying out.
It is best to sow seeds before or during the rainy season, from late fall to early spring. If rain is predicted, get out there and sow your seeds! A gentle, long rain will give your seeds the best chance of germinating. Continue sowing over a period of weeks to extend the wildflower season. In milder regions, and with certain plants, like the California Poppy, it is okay to continue seeding into spring.
It is easy to disburse large, coarse seeds, like Poppies. It is more difficult to distribute fine seeds like Lacy Phacelia. In this case, mix the seeds with sand or saw dust before broadcasting. Or, try using a kitchen spice or powdered sugar shaker. Another technique suggested by a colleague of mine is to toss the seeds gently into the air with one hand and bat at them with the other. This technique is fast, effective, and fun!
As mentioned above, it is important for the seeds to have good contact with the soil. If they are lying lightly on top of the soil they will dry out, blow away, or be eaten by birds. After sowing, rake the surface very gently. A light layer of mulch, either fine, weed-free organics (not coarse woodchips) or gravel can keep seeds from drying out and give them a better chance of making it. Some websites suggest walking on the surface to make sure that seeds are firmly in contact with the soil.
Water with a fine spray to moisten soil and seed, and improve seed-soil contact. If rain is not in the forecast, water gently to keep bed moist as seeds germinate and begin to grow. For many native wildflowers you can taper off supplemental water when annuals are a few inches tall during winters with average rainfall. Provide supplemental water in spring to extend bloom period.
It is essential to stay on top of weeds or they will quickly overwhelm the new wildflowers. When you start the garden, sow some wildflower seeds in pots to help with seedling identification. If weeds or insects are decimating the seedlings, seeds grown in pots or flats can be transplanted once they are large enough to make it in the cruel world (about four inches), though this can be a tedious process. Check Sowing Wildflowers for more pictures of seedlings of both wildflowers and weeds found in Southern California. If you sowed the seeds too thickly, you may want to thin the seedlings by hand.
- Remove wildflowers (and weeds) that are crowding new perennial plantings. Show no mercy.
- Cut flowers for bouquets, and deadhead – remove spent flowers – to extend the bloom period. Remember to leave some seeds for the birds and for next season.
- Collect seed in late spring to summer for next year’s garden but, again, leave some for the birds. Store seeds in a cool, dry location.
- Most residential gardens will look better if spent annuals are removed at the end of the season, although it is best not to rush this from a habitat standpoint. Balance between keeping your neighbors happy, yet providing for the birds.
- If you want wildflowers to reseed during the following spring, do not water during summer since the seeds will decompose in hot, wet soil.
As with all of your gardening, remember to enjoy the wildflower season. If you are a lazy gardener or one who is especially busy in late spring and summer, a large wildflower display may not be the best idea. You can grow wildflowers in containers and then hide them behind the garage once they no longer please. Or travel to California’s spectacular wildflower areas and enjoy color as only Nature can paint it.
- Mother Nature’s Backyard, Growing California Wildflowers
- Larner Seeds, The Basics of Sowing Wildflower Seeds
- Tree of Life Nursery, Seed Mixes, Planting Instructions
- Theodore Payne Foundation, Sowing Native Wildflower Seeds
If you like this blog post, check out my book, Wild Suburbia – Learning to Garden with Native Plants.
Wildflower Garden Throughout the Year
(Click on thumbnail for full picture and slideshow)