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Garden wisdom from deer country!

Gardening in the Sierra Foothills with Carolyn Singer

The seasoned gardener

published in The Union in Grass Valley CA

More information on soil preparation and mulching is detailed in Deer in My Garden, Vol.1: Perennials & Subshrubs and Deer in My Garden, Vol.2: Groundcovers & Edgers!

Iris at meadow's edgeBuilding soil fertility and tilth:
Amendments offer many choices

by Carolyn Singer
May 9, 2009

As I write, it's still raining, and it has been for days. It's my favorite kind of weather, even though it is delaying spring planting of vegetables. With this much moisture in the soil, it will be several days before serious digging can resume.

Yesterday, in the rain, I transplanted lettuce, kale, and bok choy seedlings that had been seeded in a flat a few weeks ago. The soil in the planting bed had already been prepared during a recent dry spell. Decomposing straw mulch protected the surface after I had added some turkey manure, alfalfa meal, rock phosphate, and oyster shell. The delicate young plants were slipped into this loose, friable and fertile soil with minimal disturbance.

Tomato plants and other heat-loving vegetables are thriving in my cold frame. Most are grown in two-gallon containers for optimum root development. It's rare for me to plant these vegetables into the garden until late May.

Acer palmatum Not only have I had a frost as late as June 13th, my vegetable garden site is in a "cold pocket" on Sonntag Hill. Last year, tomatoes planted in mid-May showed signs of serious nutrient deficiency a couple of weeks after they were planted. The ground was still too cold for the roots to absorb the food they needed. However, as soon as the weather warmed up all was well, and I picked my first ripe tomato July 1.

Whether you are beginning a new garden or revitalizing an old one, attention to amendments is a critical step for success. Cover crops dug into the clay soil are just the beginning. Manures added before the cover crop seed is sown increase the biomass from this amendment. A cover crop grown in fertile soil grows better! Adding poultry manure (1-2 inches) as the "green manure" is turned into the soil assists decomposition.

CA poppies Foothill soils are deficient in phosphorus, a nutrient essential for root growth, flowering, and fruiting. This means we need it for everything we grow. I use an organic form, rock phosphate, and I add a little more each year in my permanent beds. In a new area, twenty pounds per hundred square feet is a good application. Because it is not water-soluble, this amendment must be dug into the soil where the roots can reach it.

Oyster shell lime adds calcium, adjusting the soil pH and allowing other nutrients to be available. This amendment is water-soluble, and so should be added each year. Five pounds per hundred square feet is a good application rate for our foothill soils.

Hundreds of earthworms were hard at work as I planted the lettuce. They are an essential part of the amendment process. And without lots of organic material, the worms will look for a meal elsewhere. I always have a lot of decomposing straw available to keep them happy. The straw is turned into the soil and also used as a mulch on top. However, it does cool the soil, so in spring I use the straw as a top dressing only for the "cool season" vegetables, peas and greens.
light straw mulch

©2009 by Carolyn Singer. All rights reserved.

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