Originally Published: February 15, 2008 7:13 p.m.
Carpenters know the importance of preparation as in the saying "Measure twice, cut once." Similarly, a house painter carries out the most important part of a project by cleaning, sealing or masking before a brush touches paint. Gardening is no different. The old adage "Never put a $5 plant in a 50-cent hole" is one way of saying that soil preparation is the most important step of spring planting. Many beginning gardeners learn this the hard way. I can help you skip a disheartening and expensive learning experience by telling you how to prep your garden's soil before planting.
A thorough general cleaning is the first step in preparing a garden site. Remove rocks, sticks, stumps and other debris. It is especially important to kill off existing weeds. Next, lay out the boundaries of your site using string, rope or my favorite technique: with a garden hose. Then spade or till your soil to one shovel's depth.
By amending the soil in your garden-to-be, you can improve the drainage of the soil's physical structure, which is essential for healthy plants. Because sand drains freely, beginning gardeners sometimes think that sand can improve the drainage of clay soil. My grandfather taught me that by mixing sand and clay together you will make cement. The same mix will have the same result in your garden soil. It's the addition of organic material that makes the greatest improvement to all types of mountain soil. Good soil amendments are organics such as compost, aged manure, peat moss, leaf mold or similar organic materials. Never add more than three inches of organic matter to the soil at one time; larger quantities are hard to mix into the soil.
Although soil amendments may contain plant nutrients, the nutrient level is generally not high enough to be considered fertilizer. It's no secret that the plant food of choice for my garden is Start-N-Grow by Fertilome, coupled with soil sulfur which helps keep the soil's pH low for better flowers and fruits. I sprinkle the recommended amount of plant food and soil sulfur on top of the added mulch and manure and turn them all together. I'm proud to say that this shortcut of adding all to the soil with one turning is my energy-saving contribution to efficient gardening.
If you have really hard soil, consider adding gypsum and perlite to your soil. Gypsum is a natural product that helps flush soil of harmful salt build-ups that cause drainage issues later in summer. In my opinion, gypsum is a must in any tomato garden. The added calcium it brings to the soil reduces the likelihood of blossom end rot, that ugly black spot that forms on a newly developing tomato in spring.
Perlite is my favorite amendment for flower and vegetable gardens. You may have noticed white specks in a good potting soil; that is perlite. It's an organic material that helps keep hard soil from compacting and increases oxygen down at the root level.
This is how I just prepared a 200-square-foot raised flower bed in my own back yard: First, I scattered the contents of 20 1.5 cubic foot bags of organic mulch over the bed. I then sprinkled about 2 pounds of Start-N-Grow fertilizer, 4 pounds of soil sulfur, and 4 cubic feet of perlite on top of the mulch. I went over the area twice with my rototiller at the deepest setting to thoroughly combine the additives with the soil. Then I planted.
It was a terraced bed where the drainage was good so I didn't have to add any gypsum. If hard soil had been an issue, I would have added 100 pounds, which is two large bags, of gypsum.
Having followed these instructions, I guarantee well-prepped garden soil that is going to grow hearty flowers and vegetables. The garden center already has its 2008 onions, garlic and potatoes, but I must give you a heads up about some exciting early spring flowers.
When candytuft, Iberis sempervirens, shows its bridal white blooms in February we know that spring is almost here. Candytuft is in full bloom right now and ready to plant. I especially enjoy is the Lenten Rose, Helleborus, one of the first perennials to bloom in spring. Its tall upright blossoms measure 3 inches across with multiple buds already showing on each plant. Also available to usher in another gardening season are the classics: pansies, violas and English primroses. These are just some of the plants at the garden center right now that are ready for planting in that newly amended garden soil.
I would like to know your concerns, questions or thoughts about future topics for this garden column. You may submit them to me at Watters Garden Center, 1815 Irons Springs Road, Prescott, AZ 86305, or through my website at www.wattersonline.com. Just click on the "ask a question" link and type in your queries or contributions. Each comment is delivered directly from your desktop to mine.
Until next week, I'll see you in the garden center.
Ken Lain is the owner of Watters Garden Center in Prescott and a certified nursery professional, master gardener and has gardened extensively throughout Yavapai County.