Most of us in the Bay Area fight with our heavy clay soils every spring as we get ready to plant our vegetable garden. In the winter, rain causes the clay in our soil to swell, become slippery and sticky and to prevent water from draining properly. During the dry summer the soil mass will shrink, crack and become almost rock hard. Certainly not the best conditions for a successful vegetable garden! The good news is that our clay soil is composed of pre-historic ocean bottom with every mineral a plant might need, if the roots can extract them.

The soil also must be porous so that there are air spaces for the roots to get the oxygen they need and for the water to drain away and make the air spaces available. The only successful way to increase the porosity of a clay soil is by adding three to four inches of an organic amendment such as Bumper Crop, Pay Dirt, Gold Rush, Forest Blend, steer manure, rice hulls or horse manure. Gypsum at the rate of 10 pounds per 100 square feet and sulfate of ammonia at the rate of 2 pounds per 100 square feet is also spread over the area and then all plowed, dug or roto-tilled to a depth of eight inches. Horse and steer manures have practically no mineral content and so are of little or no fertilizer value. However, they still contain undigested plant material which is an excellent source of organic matter.

Gypsum reacts chemically with the clay particles and pushes them apart, making the soil more porous. Sulfate of ammonia provides nitrogen to the soil bacteria, enabling them to break down the cellulose in the plant material.

The organic matter works its way into the clay soil separating it into small globules and increasing the overall porosity of the mix. The soil becomes more sponge-like and more easily worked. Each year another inch of organic matters is added to the soil to replace that which is lost through bacterial action. We like to replace the organic matter with Gold Rush, which contains 15% chicken manure. Chicken manure has almost five times as much nitrogen as cow manure and so the sulfate of ammonia can be eliminated at this stage.

All of this preparation should be done during February or March, three to four or more weeks before planting time. It may take several years to get your soil to the porosity and tilth you desire, but it can only be done by following this procedure.

A common mistake by well-meaning but unknowing gardeners is to add sand to clay soil in the mistaken belief that sand will compensate for the clay’s density. Unfortunately, the sand sinks below the clay forming another layer. Some of the sand will also bind to the clay forming a brick-like mass.

When the same garden space is used year after year, it will be necessary to replace some of the minerals in the soil after the second or third year with a suitable fertilizer. (More on this next week!). Fertilizer is placed on the surface and worked into the top 2 to 3 inches of soil.

If your soil is an extremely dense adobe, the best resolution for the problem may be to use raised beds. Eight-inch high beds are a minimum. Twenty-four inch high beds are optimum. Raised beds can be any length but should be no more than four feet wide so that the gardener can reach to the center from either side.

When gophers are a potential problem, a one-inch by one-inch mesh of welded wire should be placed on the bottom of the raised bed and folded up the inside. Do not use chicken wire, which will decompose after 3 or 4 years. Next, three to four inches of compost is placed on the bottom. Finally, the raised bed is filled with ‘nursery mix’ to within one inch of the top. No fertilizer will be needed for the first six weeks.

Ideally, your garden plot should be allowed to ‘rest’ for one or two weeks so that the soil mass can settle. This time also gives bacteria a chance to do their work and help to combine all of your ingredients.

Soil temperature is your final concern--55°F is the magic number. When soil temperatures are below 55°F there is little or no plant growth. Wait until the soil is warm enough before planting. Seedlings planted in cold soil will just sit there and may die or produce stunted growth.

Next week look for our article on Planting and Fertilizing Vegetables.

Ceanothus may be just the plant for you! Commonly called the 'California Lilac', the ceanothus is unquestionably one of the best blue flowering shrubs available for garden use. Flowers do vary in different shades of blue, depending upon the variety chosen.

In its native environment, ceanothus grows in a sunny area, where the soil is well drained. In fact, conditions are sometimes drought-like. A south or west exposure against the house closely resembles these conditions.

Easy to grow - since it is a native, it thrives in gardens here. In fact, it seems to thrive on neglect. If a problem develops, it is usually because the plant has been pampered too much.

Uses in the landscape - as a landscape subject it is a very versatile shrub. It is available in a wide range of types, from low growing ground covers to varieties that may reach a height of 20 feet at maturity.

The upright types are often used to cover a fence or blank wall, but are also excellent as free standing shrubs. I like to use them inter-mixed with other shrubs, because of their attractive blue flowers. As free standing shrubs they are excellent for borders, foundations plantings or as evergreen screens. In addition to its use in the inland garden, ceanothus is one of the best shrubs to use near salt-water, it grows and flowers beautifully at the ocean.

Leaf texture - their leaves are small to medium in size and generally tends to be a dark glossy green on most varieties. It is evergreen. The foliage makes an excellent background for the attractive flowers.

Planting - ceanothus plants will not tolerate wet feet. So be sure to select a spot that has good drainage. When preparing the planting soil, mix generous amounts of Master Nursery Planting Mix or Gold Rush with your existing soil. Compost, processed manure and peat moss are excellent sources of organic humus.

Bedding plants are starting to roll in from our growers! New arrivals include marigolds, cosmos and zinnias. You can pair these with impatiens, begonias, lobelia and alyssum that are in stock. Strolling through our bedding area is like walking through a candy store.

Vegetables and Herbs
Tomatoes, peppers, eggplant and squash are here! Also the sweet basil has arrived. So get a jump start on your chef’s garden.

Season Starter—Early Season Plant Protector
Protect plants and extend your growing season. You can plant tomatoes up to 6 weeks earlier and harvest fruit earlier. Ideal for all vine plants and herbs.

3-pack--$11.99

Tomato Tray/Automator
Increases your harvests up to 40%--Perfect for tomatoes, peppers, and all vine crops. Warms soil for early root development, protects all vine crops against droughts and cut worms - brings earlier, tastier harvests. Ideal for: tomato plants, pepper plants, all vine plants

3-pack--$7.99

Erhard Wegman

Erhard Wegman, one of the Wegman family, is the Store Manager. Erhard’s knowledge of plants, garden supplies and plant diseases is extraordinary. You will see him behind the counter or out talking with customers. Erhard loves to track down information on the Internet and stay current on new products. Erhard is the ultimate ‘networker’; he is always happy to share his knowledge and contacts. He also holds the title of Local Tomato King, having grown over 200 varieties tomatoes!

Erhard is also active in the Peninsula Chapter of the CANGC and the NorCal Board. In 2007 he is the chairing two horticultural trade shows - the NorCal Spring Trade Show and CANGC’s Garden Market Expo Horticultural Trade Show in Las Vegas. His activities translate into the best new products we can find for our customers!