by Bill Lindelof
The Sacramento Bee
In the spring, a gardener's fancy turns to tomatoes.
The itch to buy tomato plants at the local hardware or nurseries can be overwhelming. The siren call of Early Girls and Better Boys beckons.
That might be particularly true this week as the National Weather Service forecasts sunny skies and daytime temperatures in the low- to mid-70s. Nighttime lows are expected to range from 44 to 50 degrees in Sacramento.
But hold on there, tomato lover. It's still too chilly to plant delicate seedlings. That's according to Don Shor, noted gardener and owner of the Redwood Barn Nursery in Davis.
Sure, he stocks tomato transplants in his store – but that doesn't mean he approves of planting them outside quite yet.
Shor said that before tomatoes are planted, the nighttime temperatures should consistently be above 50. Soil temperature should be 60 degrees.
"The key is soil temperatures," said Shor.
He suggests the "butt test." To do that, go outside and plant your rear on the ground.
"Put on some shorts, sit on the ground and if you are uncomfortable, the tomato plants will be, too," said Shor.
Shor is less concerned about tomatoes being planted too early than he is about peppers and eggplant. Put in a tomato too early, and the plant will turn purple and get phosphorous deficiency.
"They will sit there and sulk," he said. "Things that want to eat them will eat them. Then, when it warms up, they will start to grow. But put peppers and eggplant in too early, and they will be stunted all season. The peppers you plant in May always do better than the peppers you plant in April."
The rules with peppers and eggplant are night temperatures of 55 to 60 degrees and a soil temperatures of 70 degrees. Shor said that some gardeners use seedling blankets or plastic "walls of water" to warm plants. "Or you can do like I do – just wait," said Shor.
At times, his nursery has put up a sign near the tomato seedlings saying "It's too early to put these in the ground." That entertains customers, he said.
"I got my first request for tomatoes on Jan. 17," he said. "There had been a good frost on the ground."
Some gardeners like to buy small plants early on and shift them into larger pots for later planting. Going by the calendar, Shor suggests waiting to buy tomatoes, eggplant and peppers until May 1. "People often wonder when it is too late to plant tomatoes," he said. "You can plant them into June. We have a long season here."
What really helps warm the soil is a raised bed. Out in the open field, soil can linger in the low 50s, while the city gardener's raised bed is a toasty 62.