By Joan Bergsund
Tuolumne County has never looked lovelier. As you travel the bypass and back roads you have certainly noticed the great swaths of blue lupine, golden poppies, and even pink clover and magenta vetch. What an introduction to spring!
Because so many gardeners have expressed difficulty getting these wildflowers to “catch hold” when planting from seed, I emailed Jim von Dohlen, the landscape architect for Caltrans District 10 in Stockton. Perhaps he might share the technique Caltrans used to seed the shoulders of the new bypass as they completed the construction phase. When I wrote an earlier article about the species planted inside the wire baskets with burlap berets the wildflowers had not yet begun to bloom. What a pleasant surprise awaited us! Jim was prompt with his reply and gave me the following information.
The secret is in the seed, and the Caltrans requirements. It´s a circuitous procedure, which I summarize as follows: In order to assure the best quality the seed must be labeled under the California Food and Agricultural Code by the vendors supplying the seed, which has been tested for purity and germination within the preceding 12 months. The testing is done by a laboratory certified by the Association of Official Seed Analysts or a seed technologist certified by the Society of Commercial Seed Technologists. The seed must be from the previous or current year´s harvest, and shall include the date collected and the name and address of the seed supplier.
In addition to being fresh, all legume seed shall have been pellet-inoculated with a viable bacteria compatible for that species of seed. This process must meet the requirements of the University of California, Division of Agricultural and Natural Resources under Bulletin 1842: “Range-Legume Inoculation and Nitrogen Fixation by Root-Nodule Bacteria.” In addition the treated seed must be planted within 90 days. A small sample of the seed is tested at a quality control lab in Sacramento to verify compliance with the above requirements.
This special seed is then sprayed on the site, using a mixture of water, fertilizer, a stabilizing emulsion and other materials. The water improves an even distribution of the seed mixture, rather than serving as a boost to germination. As you may recall, this hydro seeding was done in the dead heat of August last summer, and germination was certainly not desired at that time. The mixture stayed dormant until the winter/spring rains brought them to life this spring. And what a life!
Wildflower seed is available at all our nurseries and can be purchased from wildflower seed purveyors over the internet. Look for the date to assure the seed is fresh. Perhaps in the case of lupine the package will indicate the inoculant procedure. Another technique is to gather the seed locally, after the plant has faded and gone to seed. This way, you have the assurance that the seed is compatible with our growing conditions and elevations. And for best results, order another spring with the long soaking rains we have experienced this year!
Can we have our slopes hydro-seeded like Caltrans did? There are landscaping contractors that do hydro-seeding, and they are located in the valley. Because of the equipment required they handle large scale jobs. Perhaps they would treat an entire neighborhood, or subdivision. It´s worth an inquiry if you are interested.
Now, for a spectacular display of bush lupine and other wildflowers stroll along the old railroad grade in Tuolumne, off Buchanan Road. The lupine is so thick that the fragrance is heavy on the mountain air. It reminded me of grape Kool-Aid! If you haven´t walked this path, maintained by the Tuolumne Recreation District and the Bureau of Land Management, you have a great treat in store. Run, do not walk, as the blooms will fade before long.
Joan Bergsund, a master gardener since 1996 delights in finding wildflowers popping up in the least expected places.