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Cool Soil Makes for Hungry Plants

Feed new plants or warm the soil

Like air, soil is slowly warming. When soil temperatures are below 60 degrees, soil microorganisms are rather inactive and plants have fewer nutrients to absorb. As the soils warm, the microorganisms become active and more nutrients become available.
    The conventional gardener can readily solve this problem by side-dressing with a water soluble fertilizer such as Miracle Gro or by sprinkling calcium nitrate, ammonium sulfate or a complete fertilizer near the plants and cultivating it into the soil. This practice will stimulate the plants into early growth. Never allow granular fertilizers to remain on the surface of the soil if you want your money’s worth, for some of the nitrogen will be lost into the atmosphere.
    The solution to cool soil is more complicated for organic gardens, where growth depends on the microorganisms in the soil digesting the organic matter and releasing nutrients.
    Organic gardeners can solve the problem by blending blood meal or fish oil with the soil prior to planting. Another method is to cover the area one to two weeks before planting with a sheet of clear plastic, anchoring the edges of the plastic into the ground. The clear plastic will provide a greenhouse effect and warm the soil. At planting time, remove the clear plastic and cover the row to be planted with black plastic strips 12 to 18 inches wide. Using a sharp knife, cut an X and transplant through the plastic, which will help keep the soil warm and smother weeds.
    I rely on soil test results in making fertilizer recommendations. However, testing is done at room temperature, so soil may contain adequate amounts of nutrients that may not be available in cool soils. This is why water-soluble starter fertilizer is recommended when transplanting in early spring. Water-soluble starter fertilizer provides instantly available nutrients that early spring-planted crops need for optimum growth.
    If you are transplanting plants grown in peat pots, tear away the top of each pot before planting. Allowing the tops of the peat pots to protrude above the soil will result in water being wicked away from the root ball. Plants can die of drought despite the soil surrounding the peat pot being moist. I prefer tearing away the entire peat pot to ensure that the garden soil makes direct contact with the root ball.
    If you are transplanting plants grown in plastic pots or cell packs, examine each root ball before planting. If the roots cover the entire outside edge of the root ball, crush the root ball to disrupt the root system. By crushing the root ball, you will be forcing new roots to grow into the garden soil. Allowing the roots to remain undisturbed often results in delayed establishment or stunted plants.


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