SACRAMENTO, Calif.-This tomato plant was a goner. Thinking I was helping, I only hastened its rapid demise.
How? I watered in the late afternoon. It was a hard lesson on "proper irrigation."
During a recent triple-digit heat wave, this particular tomato vine wilted badly. On an after-work visit to my community garden plot, I was alarmed by this plant's near-death appearance. Its leaves brown and curling, this little tomato looked like it had been under a heat lamp all day. I immediately grabbed a hose.
I thought a deep soaking might revive this bush and save its baby tomatoes. I was wrong.
"In extreme heat, you don't want to give a plant water, even if it's wilted," explained plant expert Kate Karam of Monrovia Nurseries. "The plant needs a chance to recover first and for the soil to cool down.
"When temperatures reach over 100, water late at night or early in the morning," she added. "Don't water in the late afternoon or you'll boil your plants' roots alive. They'll literally steam; the soil is just too hot."
That's what happened to this sad tomato. The next morning, instead of bouncing back into a green and happy bush, it drooped into a heap of crispy leaves. So much for this plant. Fortunately, its neighboring tomato vines came through the heat spell OK. This summer's harvest will not be a total loss.
This tomato death was a reminder of how many things can grow wrong in the summer garden.
Tomatoes love warmth but only tolerate high heat. That rapid rise in temperatures causes them to shut down fruit production and concentrate on survival. They drop blossoms or refuse to set new tomatoes. They develop brown spots on tomatoes that are forming (signs of dreaded blossom end rot).
To help your tomatoes make it through this summer, treat them like you'd treat yourself. Keep their roots hydrated (but not soggy) and cool. Add a layer of straw mulch or other organic material to maintain that steady soil moisture and temperature.
If triple-digit heat is predicted, even sun-loving tomatoes need some relief. Erect an umbrella to shade the vines in late afternoon or place some burlap over their tomato cages. That will not only cool the vines, but prevent sunburned fruit.
And never water in the late afternoon.