Question of the Week Number 1: March 22, 2018
“Neil, I’ve not had very good luck getting tomatoes to set fruit in the past. What can I do differently?”
Proving the negative (why something doesn’t happen) is always difficult, but I’ll give you the most likely causes.
1. You chose the wrong varieties. Large-fruiting types like Big Boy and Beefsteak were bred for areas with cooler summers. They do not set fruit well when temperatures exceed 90 degrees in the daytime. Stick with small and mid-sized varieties. Some of the best include Celebrity, Roma, Porter, Sweet 100, Red Cherry, Yellow Pear. While not as good as some of the favorites we no longer have, Super Fantastic, Better Boy and Early Girl, are better than the large ones.
2. You planted too late. Aim to set vigorous transplants out one to two weeks after the average date of your last killing freeze for your area. If you plant later, summer’s heat will catch up with you.
3. You planted in too much shade. Tomato plants need full or nearly full sun (10 hours each day during the summer) to bloom and set fruit to their maximum potential.
4. You didn’t have good air motion around them. That’s critical for mechanical vibration of the stems and leaves. It’s that movement that shakes pollen loose within the flowers, thereby assuring good fruit set. If you want to improve things, just thump the flower clusters every couple of days to help the pollen shed within the flowers.
5. You didn’t keep your plants vigorous. Tomatoes need consistent amounts of water and nitrogen to keep them growing strong.