Despite working predominantly in ornamental—especially naturalistic—horticulture, I hold an “interdisciplinary minor in organic agriculture” from Colorado State University. Early in my career I worked primarily in food crops, and before I was 20 years old I spent summers in bean-breeding fields, diversified food-cropping systems, and home gardens. Through my years of food gardening, I’ve found that growing tomatoes even at 5,000 feet here on the “Front Range” is a gamble. With frequent cool, wet summers or late spring frosts—or worse, early killing frosts in fall—ours is not a favorable region in which to grow classic, meaty tomatoes.
Despite that, the gamble keeps many of us going. Last year, I had garden-grown tomatoes on the counter well into November. For mountain areas, the odds are even stiffer! My aunt and uncle two hours to my west in North Park see an average of less than 40 consecutive frost-free days each year. For a garden like theirs, tomatoes aren’t a terribly practical crop. But for many who fall between Fort Collins’s 140+ of frost-free days and the paltry 40 of our coldest mountain parks and valleys, there are options.
One of the most cost-effective tactics is to simply select cool-tolerant varieties, or those that produce fruit quickly. You may need to grow these plants from seed, but that relative cost is still less than a full blown, season-extending greenhouse. As for selecting varieties, look for tomatoes indicated to be “cool-weather-adapted” or “very short season.” It is important to note that these varieties are still frost-sensitive like other tomatoes. However, their unique designation describes their increased vigor at cooler temperatures (i.e., they are more resistant to the cool-weather
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