I believe I may have cracked the code for getting a full summer harvest. In the last two seasons the temperatures were so erratic that our usual growing season was shortened by at least six weeks. If you’ve gardened for decades and suddenly the rules get changed, the frustration is big.
This time last year I had transplanted my summer vegetables into bigger pots and was holding them in a make-shift greenhouse. This year the summer vegetables are already in the ground and growing just like it was summer.
Vegetables are very specific about the temperatures they need in order to grow a crop. Those vegetables do not flex with erratic weather. The gardener must be flexible. I’ve flexed like one of those slinky toys the kids love and it looks like my flexing is finally paying off.
Air Temperatures
We have been having lovely warm days. All the vegetables enjoy this weather but the night temperatures drop into the low forties and high thirties. The beets are fine with this arrangement — they seem to thrive. But you cannot leave a tomato out in those night temperatures. The poor plant smiles during the day and then goes into shock at night. The tomato plant will probably survive the trauma, but it will not grow and vine and flex its little tomato muscles. Most of its energy goes into just surviving.
A common practice in this area has been to cover tomato seedlings with translucent paper hot caps. This works fine for a couple of weeks until the plant is too big for the cap. If the temperatures have not risen, the now-uncovered tomato plant will sit shivering, not growing.
This year I have planted tomatoes in a bed that is a miniature hoop house. The translucent plastic that covers the hoops at night protects the bed from dropping temperatures. If the daytime weather gets cold, I leave the plastic in place around the clock. Usually I uncover the bed in the day to keep it from over-heating and cover it again in the early evening to keep it warm overnight.
Soil Temperatures
When the warm days of summer arrive, you tend to not recognize the soil still being cold. If you were a summer vegetable, you would definitely notice. Most of the summer vegetables will not start growing well until the soil temperature is nearly the same as the air temperature. Did you know that it takes six weeks for the soil to warm up to that level?
Here’s the key: Start warming the soil well in advance of your proposed planting date. I’ve done it two ways:
- Prepare your bed with amendments and other soil-building work and then cover the bed with 6-mil black plastic. Weigh the plastic down so it stays in place. I usually use old metal fence posts for this. Do this six weeks before your planting date and the soil will be warm and ready. A couple bonuses with the plastic is that it keeps the moisture in and the weeds down. Pull back the plastic and you are ready to plant.
- Put hoops across your prepared bed and cover the bed with translucent 4-mil plastic. With a hoop bed, both the air and the soil warm up. This year I have planted tomatoes in a hoop bed that was stuffed with cool weather vegetables a few weeks back. I planned my harvest of these cool weather vegetables to create open areas to plant the tomatoes. Pulling a plant leaves a hole. I fill the hole with compost and plant the tomato in the compost. By the time the tomatoes get bushy, all of their beet and garlic neighbors will be gone. I will fill those holes with compost as a side-dressing for the tomato plants that will probably be as tall as me by then.
This is the start of a great tomato summer!
