Purple coloration usually indicates a phosphorus deficiency. Phosphorus deficiencies occur early in the growing season when soil is still cool. Phosphorus is abundant in our soils but may be unavailable to the plant when the soil is too cold. Two additional problems may coexist: poor drainage (drowning roots) and/or soil pH out of range for this crop (have soil test preformed). Try not to plant tomatoes too early in the season. Tomatoes grow better in warmer temperatures. Once soil temperatures rise, the problem usually corrects itself. Your other vegetables should grow larger with warmer temperatures, too. If you decide to replant the tomatoes, choose an early variety to have some reach maturity before frost in the fall. Putting down straw to hold back the weeds is a good idea. It's best to wait to apply the mulch until the soil has warmed - usually in early to mid-June, depending on the weather. Mixing organic material into the soil this fall is also a great idea. Manure and compost are good choices.

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