Great Tomatoes Every Year

Bob Randall with his May 2020 Harvest of backyard tomatoes.

By Bob Randall, Ph.D.

At our house we taste the wonderful bounty tomatoes offers us very spring.  The reason is that tomatoes begin to ripen on the vine in April and although perishable and hard to ship ripe, are fairly easy to grow if you follow a few rules. I get a lot of questions from beginners every year because the challenges of growing tomatoes successfully are widespread.   But you can overcome them if you do a few things right . 

Here I’ll try to answer four common questions:

Q. I have lots of flowers on my tomatoes but no fruit.  What’s wrong?

Answer: Timing & Varieties. Your flowers aren’t pollinating because the pollen is sterile when daytime temperatures are over 85˚F or night temperatures are above 70˚.  You probably planted too late. 

In most of Southeast Texas there are 4-6 weeks in the spring when temperatures are over 50˚F and below the maximums for pollination.  So, your plants need to be full of flowers during these weeks. Once the flowers set fruit, they will ripen even if temperatures are hotter, so the tomatoes you eat in summer set fruit in cooler temperatures.  In spring, depending on your location, proper temperatures for pollination fall between late March and early May.  In the fall, in areas that don’t get November or early December freezes or if you use plastic hoop-houses, cherry tomatoes will often set fruit from late September to mid-October or later.

There are several things you need to do to get this timing right.  First, it is much easier to get lots of flowers at the right time on so-called early season or mid-season tomatoes, than it is to get early flowers on so-called late varieties like many delicious heirlooms. Also, there are lots more flowers on cherry tomatoes than there are on beefsteaks, and more flowers on so-called indeterminate tomatoes (that keep on fruiting up the stem) than on determinate ones that fruit all at once.  Good early season varieties include the yellow hybrid cherry Sun Gold and the non-hybrid heirloom red plum tomatoes Bloody Butcher and Stupice.  Many mid-season varieties work also.

Backyard tomato garden and photos by Claudia Sanjuan.
(She took the online Tomato in Fall and Spring webinar and shared her success!)

My recommendation is to figure out when in the spring you regularly have these temperatures. 6 weeks before the start of these temperatures, put cold protected transplants in the ground.  And 4-6 weeks before that, start seeds in a room under lights or in a greenhouse at 60-80˚ temperatures.  In the southern part of Houston, I start seeds indoors under lights the first week of January and put highly temperature protected transplants outside the second week of February. 

Your dates may differ if you are further from the Gulf or closer to it than me, or if you are more urban or less so. In my 2019 book Year-Round Food Gardening for Houston and Southeast Texas, there are planting schedules for tomatoes and other veggies at all locations in Southeast Texas from Galveston to Crocket and Beaumont to Columbus.

Q. Leaf-footed Stinkbugs are Wrecking My Tomatoes.  What can I do?

Answer: Trap them.  Generally, organic gardeners don’t turn to poisons to solve pest problems.  Rather, we ask, “Why doesn’t the pest have a pest?” and do what we can to welcome pest predators and parasitoids. But in this case neither poisons nor predators work well, so our victims are our tomatoes and us.

What you can do is plant asparagus beans (long beans or yard-long beans) on a six foot trellis this spring and pick the bugs off the beans about 8 am in August.  On long beans, leaf-footed bugs are easy to catch and dispatch by sticking them in soapy water. They have relatively low reproduction rates, so if you work at it for a while, the numbers next spring will be small.

Q: The Birds Get My Tomatoes Before They Fully Ripen

Answer: Pick them when they are partially coloring up.  Once yellow tomatoes begin to turn yellow or red tomatoes red, they will ripen just as well or better off the vine inside protected from varmints (provided of course you keep away the roaches).  Light green tomatoes will also ripen but will never taste as good. They ship well though. Once inside, keep them out of the refrigerator and eat them when they are full golden orange or deep red.  Birdbaths will also keep away birds that are just thirsty.

Q. I’ve Got so Many Other Questions

Answer: Some yearsI answer questions at the Urban Harvest Tomato Fest in June. This year, stay in tune to the Urban Harvest E-news for updates on the new Tomato Fest reimagined. Sign up for the Urban Harvest e-news letter here. And for an in-depth lesson take the Growing Tomatoes in Spring and Fall Webinar Urban Harvest is offering for free.

I will be co-teaching an online Fall Organic Vegetable Gardening on July 18, 2020 for Urban Harvest and a 10- class course, Growing Organic Vegetable series twice a month January-May on Thursday evenings, new this year,  online.  My new book has a lot more suggestions for excellent tomato growing.

Year-Round Food Gardening For Houston And Southeast Texas, By Bob Randall, Ph.D, can be found for sale at the Saturday Urban Harvest Farmers Market greeters booth.