Organic Gardening Info from Peaceful Valley

Question:

Hi,

I can’t find enough information on your website or recent printed catalog to figure out which erosion control seed to use.

For three years I have tried the Santa Cruz County Erosion Control mix with poor results.

I am trying to seed the following conditions:

Santa Cruz mountains at 400′ elevation. South facing slope but in a valley with heavy shade in the winter. Steep slope eroded with thin soil on a silty mudstone. Trees overhead and/or just upslope are douglas fir and mixed hardwoods including Bay, Madrone, Tan Oak and other oaks.

I don’t intend to water at all and have put down rice straw on bare areas. The area stays moist for 2 months after the rain stops. Rainfall about 30″ / year.

I suspect that the douglas fir and/or oak litter is the problem for seed generation. Is there any ground cover that is known to work under oaks and douglas fir?

Would prefer plants that develop deep roots and provide complete ground cover.

Any suggestions appreciated.

Thanks,
Santa Cruz

Answer:

This is a challenging situation.  I’m sure that oak litter would be a problem for germination depending on what time of the year you are seeding.  It’s heavy shade in the winter? Can I assume it’s shady when the trees are fully leafed out?  Do you get some sun in the spring/summer?  If the seeds are planted to deep or under to much mulch they won’t germinate.  You may have some luck with our Low Growing Clover Mix, the white clover tolerates shade and the strawberry tolerates heat.  These would provide erosion control and decent root systems.  They may die out without any water in the summer however.  One of the annual clovers may work too.  But with no sun and leaf material covering the seed you have a difficult growing situation.

I hope this helps.

by Amber TIppett, PV Store Manager & Willow Hein, FreshmanFarmer & PV employee

“Cover Crop” is a general term referring to a crop grown to cover and protect the soil. The term “Green Manure” would more specifically apply to a Cover Crop grown with the intent to till back into the soil. Below we’ve outlined a few Cover Crop Solutions for clay or compacted soils, vegetable bed rotations & erosion control. Looking for more solutions? Check out our Cover Crop Solution Finder.

Cover Crops (or, “Green Manure” crops) for Clay or Compacted Soil

Planting cover crops is an excellent way to help break up compacted and clay soils. Plant something with a large taproot, or deep reaching root system that can penetrate the hard soil or compacted soil pan. Examples of these include Bell Beans (SCL700), Winter Rye (SCN395), Rape (SCN900), Daikon (SCN112) and Mustard (SCN755 or SCN750). You’ll want to plant these cool weather crops in the fall after the first rains when the soil is softer and can be tilled and prepared for planting. The cover crops will grow all winter, and then can be turned in during the spring to add organic matter to the soil. The cover cropped area can then be planted with vegetable or ornamental crops, or planted with a summer cover crop to continue breaking up the soil if it is still too compacted. Examples of good summer cover crops for this purpose are Crotolaria Juncea (SCL815) and Sesbania (SCL855). You will need to irrigate these crops through the summer if you live in an area where it doesn’t rain.

Cover Crops (or, “Green Manure” crops) to plant in a Vegetable Rotation

Planting a winter cover crop is a great way to replenish your soil after a season of vegetable or production cropping. You want something that will fix nitrogen back into the soil, hold the soil in place during winter storms, and grow vigorously for maximum organic matter and weed suppression. Peaceful Valley carries a great cool weather cover crop mix (Soil Builder SCM120, SCM121) which contains bell beans, winter peas, purple vetch, common vetch, and cayuse oats, a blend that addresses all the above-mentioned needs. The bell beans, peas, and vetches are legumes that fix nitrogen from the air through a symbiotic relationship with a group of naturally occurring soil bacteria known as rhizobacteria. The bacteria form nodules on the roots of the plants and convert gaseous nitrogen into plant-usable nitrogen. Be sure to inoculate (ISE350, ISE505, ISE500) your seed with the rhizobacteria before you plant it to make sure this process happens in your cover crop. The oats provide scaffolding for the vetch to climb up and have fibrous root systems that suppress weeds and help with erosion control. Other great cover crops for the winter include clovers and alfalfa.

Cover Crops for Erosion Control

Erosion of hillsides can be a major problem in some areas, and should be a concern to anyone who wishes to protect valuable topsoil. Erosion control mixes typically consist of annual grasses and clovers that have extensive root systems and strong reseeding abilities. The Premium Erosion Mix (SEC300) has wildflowers in the mix to enhance the beauty of the area. Individual varieties of seed for erosion control include Crimson Clover (SCL310), Ryegrass (SCG560), BlandoBbrome (SCG150), and Zorro Fescue (SCG299). Timing is an important issue in establishing an erosion crop. It should be planted in the Fall while the soil is still warm, and be given supplemental irrigation until the natural rains can take over. If supplemental irrigation cannot be provided, the area should be covered with Jute Netting (EC400) after it is seeded. If irrigation will be provided year round, then perennial grasses or clovers can be planted instead of annuals.

We are a non-profit Association tasked to restore a lake area that recently underwent mastication. We are located at 1,200 feet in Shingle Springs, CA (Cameron Park area). We wish to plant erosion control mixes as well as wildflower mixes (some areas). The approximate area to be seeded is 3 acre of erosion mix and 1 acre of wild flower mix. Water is only that of annual precipitation. Some areas to be seeded are picnic areas with foot traffic.

Can you please advise an appropriate product(s) and the best time of year for introducing selected product(s) given the above information.