Spring is in the air and for greenhouse growers’ thoughts turn towards planting tomatoes. Tomato plants whether lovingly propagated, gifted or bought are all subject to the same natural laws, in this case rooting temperature. Tomato plants WILL NOT grow new roots at a soil temperature below 59 F –14.5 C. How often do we hear “My tomato plants don’t seem to be growing”. That’s because they are not. The top 1″of soil may be ‘aired’ but 4 -6 inches down the temperature may be 45 -50 degrees. A Soil thermometer is a very useful tool, (Birthday or Christmas Present ?) but it needs to be used carefully and placed some 4″down in the border.
If it is too cold to plant, try ridging up the soil. In most cold greenhouses it is worth doing this anyway a week to 10 days before planting day, this will expose a greater area of soil surface to warm up the bed, then this can be raked down ready for planting. Warm moist soil allows for a rapidly developing root system and the plants are off to a flying start. The same goes for outdoor plants too. Now is the time to be sowing outdoor varieties to ensure a big plant for planting after the last frost. This year there are some lovely outdoor Blight Resistant varieties available, ‘Mountain Magic’ is delicious.