WASHINGTON — It’s Tomato Planting Time!
Maybe. Lots of itchy fingers out there! Many listeners write that they want to put their tomato plants in the ground, and many have already done so. Just remember that it’s not the daytime temps that count with tomatoes, peppers and the other crops of summer. It’s the nighttime lows that can shock the plants and dramatically slow their growth.
Nights in the 40’s won’t kill your plants as impressively as frost, but it will stunt growth, and they will resent you like ungrateful children the rest of the season.
Nighttime temps are always warmer in the heat sink of the city, so it’s safer to plant a little early in D.C. proper. But if you’re in the suburbs, nighttime temps could still drop into the low- to mid-40s, so be patient. Early planting often equals late tomatoes.
Compost Goes on the Surface; Not in the Hole
Jarrett in Fredericksburg has a question about compost and tomatoes. He writes: “I generally dump a shovelful of compost in the hole prior to planting. Is this a good idea? Or should I spread the compost around the plant?”
You absolutely want that compost to be applied as a two-inch deep mulch on the surface of the soil, and not placed down in the hole, Jarrett. Compost applied to the soil surface will deliver a nice gentle feeding to your tomatoes every time it rains, and it provides a physical barrier against disease. The living organisms in compost eat disease spores to protect your plants against evils like late blight. Whatever you do, don’t mulch with wood or bark; wood mulches breed plant disease.
Location, Location, Location!
When you plant your tomatoes, be sure to choose an area that gets morning sun; tomatoes, roses and other disease-prone plants do best when they’re planted where the sun can dry their leaves off first thing in the morning. Never wet the leaves of your plants in the evening; if you must wet the leaves when you water, do that watering in the early morning.
Don’t plant your tomatoes in the exact same spot where tomatoes have grown the past few years or they will suffer from a soil-borne wilt that causes the plants’ leaves to turn yellow from the bottom up.
If you have no room left to rotate to, plant in containers this year or try to find grafted tomatoes whose rootstock is wilt-resistant. (Resistant tomatoes in general will have the letters “V” and “F” after their variety names.) Grafted tomatoes are being offered at more garden centers every season, so look around. And whether its grafted tomatoes, grafted roses or grafted fruit trees, always keep the graft well above the soil line.
Two Tomatoes Walk Into a Bar