Draft - work in progress, 4-23-10
for gardens in the Santa Rosa area by Marlena Hirsch
Where to Plant
Most vegetables want a sunny site. Generally six hours a day is adequate. Some late afternoon shade is ok especially for leafy greens and plants in the cabbage family like broccoli. In fact, some gardeners put shade cloth over crops like lettuce when hot weather threatens. Arrange the plantings so that tall plants like mammoth sunflowers and pole beans are on the north side of the garden to prevent shading.
Preparing the Soil
A raised bed originally referred to the way loose freshly dug and forked soil is higher that the surrounding soil. In fact, there were no redwood boards holding soil when the French Intensive/Bio-dynamic method was introduced to North America by Alan Chadwick in the late 60s on the UCSC campus. Some gardens with steep slopes do need boards to hold soil.
Clay soils like adobe are actually very fertile and hold water for a long time, but when wet, they are like glue and when dry, they are like cement. They can be worked for about two weeks in the spring and possibly in between rainy spells in the winter. The only way to tell when this kind of soil is ready to work is to try to break it up with a fork or a shovel. If the soil comes apart, it is ready to work. Adding a two inch layer of organic matter like compost provides plant nutrients and improves soil making it easier to work in the future.
Watering
To illustrate a very important principle of water behavior, let’s consider container plants. Sometimes as a container plant is being watered the water is running out the bottom. This occurs when the soil has become completely dry. This dry soil will need to sit in a saucer of water and slowly re-hydrate. The amount of hours needed for the soil to reabsorb water will depend on the amount of soil.
Water is attracted to itself at a molecular level. You can slightly overfill a glass and see a layer of water above the top of the glass. The surface film of the water holds this water together. This is part of the chemistry of water that allows water striders to walk on water and cooling water vapor to form drops. There are weak positive charges on the two hydrogen atoms and weak negative charges on the oxygen atom in a water molecule. The positive charge always wants to be near a negative charge.
Understanding this principle can spare a person from feeling like their black thumb killed a potted plant. It is likely that the plant dried completely, and water ran right through the pot and not a bit went into the soil.
Dry soil can act as a barrier to water. Sometimes drops or small spoon fulls of water will sit on top of soil at first. If the soil has some moisture in it already, the water goes right into the soil. Sprinkling the ground in the summer can cause puddling on the top and no water to the roots. It is a good idea to use a shovel and check to see how deep the water is penetrating.
Water Conservation
Because of dry soils ability to make a moisture barrier, it can be used as a mulch over moist soil. In my description of “Mike’s Method for Starting Large Seeds” in “Seed Starting”, dry soil is used this way. When I was a child in Watsonville, California, apple farmers used dust mulches to hold in the soil moisture. The soil would be worked with fine harrows after initial plowing with discs. The result was a fine dust. This was done early in the spring after the rains stopped. The timing was important as you wanted to trap the moisture in the soil soon, but you didn’t want a late rain to crust the soil after it had been worked to a fine consistency. In later years, farmers used irrigation in summer, and dust mulching was forgotten.
You can read about dry farming in Steve Solomon’s book, Gardening Without Irrigation: or without much, anyway. This is available on his web site, www.soilandhealth.org.
Steve kept his soil hoed so it was always loose. He lived in Oregon at the time where his garden received no summer rain. He watered with drip systems from a five gallon bucket that had a hole near the bottom so the water slowly dripped out without wetting a large area of soil. In my Sonoma County, California area, I hear that nearer to the ocean where it is not as hot people dry-farm tomatoes. I am anxious to try this on some good clay soil that holds moisture better than my gritty mountain soil that seems to have once been a stream bed.
Spacing the plants you are growing so they form a canopy and covering soil with mulch helps to conserve moisture. Mulch can be leaves or partly finished compost. Anything with larger air spaces than your soil can be used as a mulch, even soil worked so it very loose and fluffy can be a mulch. Mulch also helps to control weeds.
Watering in Specific Situations
During hot spells, water cool season plants like lettuce, other greens, cabbage family plants, and peas twice a day. Clay soils made of small particles, can be watered deeply once a week. Sandy or gritty soils, made of larger particles, need to be watered at least every other day.
Seed Starting
In general, seeds are buried about twice the diameter of the seed.
Plan your seed starting so that warm season plants like tomatoes, beans, squash, peppers and melons are outside after May first. Peas and potatoes are planted outside around March 15th. Lettuce and other greens can be sown every month. A cover of glass or row cover cloth will protect them from hard frosts from about December through late February or March.
Mike’s Method for Large Seeds
Mike Rossi worked for Imwalle’s Gardens years ago and taught me this easy method.
Make a depression. Water the bottom of the depression. Place the seeds on the wet ground. Cover with loose soil that wasn’t watered. Do not water until the seeds come up. The loose soil acts as a mulch and keeps the wet layer from drying. If you water, the top of the soil becomes crusted and can prevent seeds from coming through.
Carrots
These small seeds can need three weeks to sprout. It can be difficult to keep the seeds constantly moist for this long. The bed can be covered with a burlap bag that helps hold the moisture in. They can also be sprouted on a moist paper towel on a plate with a plastic cover. Once sprouted, they can be spread on the soil and raked gently into the soil or covered with soil. Try to sprinkle the seeds over the soil so that they are not too close together as carrots need about two to three inches between plants.
Lettuce
Most lettuce seeds require light to sprout so don’t cover them. Once this seed becomes warm on a hot day, it may need to spend a couple of weeks in the refrigerator before it will sprout again.
Living with Small Plant Eaters
Most insects and other small invertebrates do not eat enough to do much damage when an ecosystem is in balance. For example, one year I didn’t have time to spray the aphids off the new rose buds with a blast of water. Their numbers increased dramatically. Soldier beetles came and ate them before I got a chance to spray with water. This balanced ecosystem worked beautifully.
A snail bite of a seedling can kill it. At night with a flashlight, you can find and remove or crush snails easily. This is when they are out of hiding and active. A few nights of this will make a big difference. Ivy and boards are favorite hiding places. Remove boards when possible.
Spacing
In general, the more space the roots have, the more water they can seek out. If you are short of water, give your plants more space.
When a seed first sprouts, it is very vulnerable. A day of hot 100 degree weather can dry the seedling if it is not watered. A snail can take a bite and finish off the sprout. For these reasons, plant 5 or 6 seeds to get one squash plant. These are large plants spaced at least 3 feet apart. After the squash seedlings have their first true leaves, you can leave the strongest two. Extra plants can be given away or moved to another spot if you can move them carefully without disturbing the ones that you want to keep. Leave just one plant, only when it is very strong.
Remember that one seed can mature into a full grown plant is if has the space. Picture the size of the plant and allow enough room for it to grow. The seed package will give you the spacing distance. Thinned plants of greens are good to eat.
Giving Back to The Soil
Vegetable waste from the kitchen, leaves, and grass clippings are potential fertilizer for your plants. Letting this matter decompose in a pile of 2-3 inch alternating layers of dry and green plant material with soil every two layers is how to build a compost pile. The alternating layers are important. Have you ever stepped on a pile of decomposing grass clippings? It is disgusting slime caused by anaerobic decomposition which means rotting without air. This is preventable by mixing larger dry stems, leaves and soil with grass clippings as this mix allows air to get into the pile. The soil provides the bacteria, fungi and other decomposers.
The whole pile needs to stay moist but not wet. A plastic sheet helps hold in the moisture during the summer.
Any size compost pile is good. Once a compost pile reaches the size of a three foot cube, it will generate heat. The heat helps kill weed seeds and disease causing agents. This might be very important if you were composting a manure from a mammal that might contain eggs from an internal parasite that can use humans as a host. In that case, a large pile that could reach high temperatures would be important.
Compost piles tend to be hot on the inside about 6 inches deep. Often the outsides of a pile do not compost as quickly as the warm moist material on the inside. To get uniform composting, compost piles can be turn and mixed. They can also be covered with soil or a combination of soil and grass then covered with plastic in the summer. I don’t turn my piles so I remove the material that has not decayed from the top of the pile and put it in a new pile. The well composted material is usually just under that layer.
Sometimes I have broken open a compost piles that had dried out in the middle and stayed that way. Just like watering soil, once compost is bone dry, it will take a soaking to rehydrate it. This dry material won’t be finished.
Compost is finished when it looks like soil. This takes about 2-6 months depending on the outside temperature, size of the material, and moisture content of the pile. Oak leaves and other thick leaves take two years to compost. They need a separate pile.
Rotating Plants
Replant a bed with plants from a different plant family as similar plants need the same nutrients. Tomatoes and potatoes are in the same family.
You can also alternate with a winter cover crop of vetch, mustard, peas, bell beans, and/or clover. Many of the plants just mentioned are from the legume family, as these plants produce nitrogen in their roots with the help of special bacteria. Other plants are not able to do this and need nitrogen. These legumes give up their nitrogen when they decay. A cover crop of legumes does not need to be composted. It can be buried in the soil before replanting along with any green grass growing with it. Low growing white clover can be grown in the paths.
Harmonious Plantings
Certain flowers, like alyssum, attract insects that keep aphids and other pests from causing damage. A lettuce farm in Watsonville has a row of the honey scented alyssum for every five rows of lettuce. The small florets of Queen Anne’s Lace, Bishops Flower, Verbena bonarensis, and dill attract tiny wasps that prey on leaf eating caterpillars. By encouraging a variety of plants, flowers and aromatic herbs, balanced insect life is maintained.
This type of gardening is beautiful and over time, can be relatively pest free. Remember that a few small pests do not eat much. An application of a toxic pesticide disrupts this balance.
For further knowledge, I recommend John Jeavon’s book, How to Grow More Vegetables. John has diagrams that show how to double dig a bed and layer a compost pile.
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