The function of this series, which will ultimately cover at least 80 commonly grown varieties of plants grown for food in USDA zones 5 & 6, is to provide the reader with a concise and authoritative source of information such that, if these facts are accounted for, success is all but assured.
In time, these will be refined and rewritten so as to make them shorter and more easily digestible but, for the moment, spring is upon us and so is the need to get things into the ground in the very near future. This being the second in the series, let’s jump in where we left off.
Soil & sunlight:
Tomatoes want 65° F (18° C) to germinate and should not be planted outdoors until the soil is at least 50 F.
If the germination temperature is too low, fungi & molds will invade and kill the seed before it can sprout. If by some miracle the seed does get sprouted but the temps continue cool and humid, ‘damping off’ will occur in which the sprout collapses at the soil line and dies.
Check the outdoor temperature with a soil thermometer or wait for the yellow forsythia to bloom in your neighborhood. The forsythia is an indicator plant that actually gives a good count of the total degree days and soil temperature.
Tomatoes will not set fruit until nights are at least 55 F, with much better results at 70-80 F. Like most vegetables, tomatoes only truly thrive in full sun.
Spread / Height:
Determinate tomatoes will generally spread 3-4′ and, if staked, come to about the same height. Indeterminate tomatoes should be given 2-3 feet in the row and will grow at least 6′ in most circumstances and as much as 12′ (in Detroit) given exceptional circumstances. For indeterminate varieties, use heavier staking than might seem required … a healthy crop of tomatoes is heavy and, being so tall, they catch the wind readily. I base this observation on having a row of tomatoes standing roughly 8′ tall topple, breaking their 2×2 stakes in the process. Either use multiple stakes per plant or use heavier stakes. Mine now grow on wire fencing attached to 2×4′s spaced 4′ apart. So far, so good.
Bonus tip: Always ‘harden off’ young nursery stock, whether home grown or purchased. Just set the plants outdoors in a sheltered and partially shaded location for progressively longer periods each day until the weather permits planting in the garden.
