Basics of Sowing Wildflower Seeds
Lifecycle of an Annual Wildflower:
Below is a simplified description of the lifecycle of an annual wildflower. This sequence is an essential model when growing California's annual wildflowers.
1. Seed germinates with the fall and winter rains (or the gardener’s irrigation)
2. Roots and basal leaves grow through the winter
3. Plants come into bloom from early spring to late summer
4. Flowers ripen into seed through late spring, summer and fall
5. The “annual” cycle is complete and begins again
This cycle can be manipulated by sowing earlier or later and providing irrigation. Do not thin plants; in nature they grow closely together, which encourages bloom. We keep some species blooming even into October.
Wildflowers in California's Ecology
Spring in California used to mean wildflowers. Intoxicatingly beautiful hills and meadows covered with richly and delicately-colored wildflowers of all shapes, sizes, and hues, one of the wonders of the world, judging from the remnants still to be seen, and from the reactions of early settlers. For example, in 1850, Jeff Mayfield and his family first encountered the San Joaquin Valley:
"As we passed below the hills the whole plain was covered with great patches of rose, yellow, scarlet, orange, and blue. The colors did not seem to mix to any great extent. Each kind of flower liked a certain kind of soil best, and some of the patches of one color were a mile or more across...My daddy had traveled a great deal, and it was not easy to get him excited about wild flowers or pretty scenery. But he said that he would not have believed that such a place existed if he had not seen it himself."
Traditional Planting Time
Traditional planting time is October through February, but wildflowers are adaptable to many different planting regimes, and there is a broad planting window, especially on the coast. Some even swear by late summer sowings, allowing the seeds the chance to bake in the sun. Here in West Marin, we can sow as late as April. Seed sown in the spring after rains are past will require irrigation till the seeds have germinated and made early growth. Some afternoon shade is helpful for late-season sowings. Here on the coast, we sow seed in four inch pots through the year for regular planting in the garden.
Weeding: A critical factor in reintroducing annual wildflowers is weed control. If the native wildflowers could out-compete weedy species, we would still have scenes such as Jeff Mayfield (above) and other early observers described. Like all annual seeds, wildflowers require a good seed-bed with firm seed/soil contact, consistent moisture, and freedom from weed competition. For detailed descriptions of different ways to control weeds and prepare seedbeds, order our Notes on Growing Wildflowers.
Intimidated by broadcasting seeds? Some gardeners sow in flats or pots, where the environment can be controlled, then transplant the wildflowers into their garden thru the planting season. A good way to learn what you like and what works in your situation.
Seed can be bought in bulk and broadcast in meadows, resulting in wildflowers for bringing into the house, for personal adornment, for sitting in, lying in, luxuriating in. They can be planted as garden annuals, carefully chosen to provide your favorite color scheme or randomly for a wild potpourri of bloom.
A frequently asked question is: Should I plant on top of or underneath the mulch? If you are mulching with gravel, drop seeds into the gravel after it is spread. Use the blunt side of the rake to jar the seeds into holes in between pieces of gravel. A light tilling may be useful beforehand. If you are mulching with wood chips, pull the chips back and plant in the soil lthat was underneath. It will be slightly improved by being covered with woodchips. Cover the seeds with compost/humus/soil to twice the diameter of the seed, approximately. Walk on it or roll it to ensure good seed/soil contact. Water well and expect germination in 10 days to 3 weeks. Consistent watering twice a week will get your sowing off to a good start.
Companionable Combinations: We never can decide which is our favorite way of planting wildflowers Our mixes provide months of lovely color, reseed vigorously, and are an excellent way to educate yourself in wildflowers. On the other hand, planting in swathes is also enticing and allows more control. We have seen many natural meadows with each species growing by itself. Try the subtle color variations in yellows, lemon yellows, oranges, and bright yellows with a planting of tidy tips (Layia platyglossa) with California poppy (Eschscholzia californica), goldfields (Lasthenia glabrata), and blazing star (Mentzelia lindleyi), all in the yellow-to-gold range. Little pools of clear blue baby blue eyes (Nemophila menziesii) can add a soft contrast to this lovely sunny combination.
In a good wildflower year in California, innumerable combinations of species in different proportions are found throughout the state. The variations even among the remnants of a former glory are mind-boggling in their different kinds of beauty. Even the good wildflower years are never the same. Inspiration awaits.
For more information, we offer Notes on Growing California Wildflowers in our "Notes on Natives" series, found in our Books menu item.