Question of the Week © 2017 Mike McGrath
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How to have the first ripe red tomatoes on the block
Last week, Jim "near Chicago" asked about the earliest fruits he could grow. We named strawberries, honeyberries and Serviceberries as the earliest maturing true (as in sweet) fruits, but then thought, 'what if he means fruiting plants, like tomatoes?' So we promised a follow up this week—although I teased the answer by saying "Start the plants indoors under bright lights two months before you're going to plant them out, use season extending devices to put them out early in the season, choose varieties labeled 'early' or 'cold hardy' and you can pick tasty little tomatoes by the fourth of July."
Really. Even near Chicago. And this topic also touches on the reason a huge number of people contact us every year freaking out because "all their tomatoes are still green" in August.
Without even asking, I always know that it's because they're growing the 'wrong' varieties. Now, that's not 'wrong' in the 'great tomato' category—in fact they're often growing the absolute hands-down best-tasting varieties. The issue is that those varieties are generally big heirlooms with the longest possible 'days to maturity'.
Let's use Brandywine as an example. It's considered by many to be the best-tasting heirloom, but it's a big tomato that is famously slow to ripen, with an average 'days to maturity' rating of about 85 days. (I got that number by averaging the dates from four or five different catalogs; nobody had the same number, and many used a ten day range.) And that's not 85 days from seed; with tomatoes, peppers and other pre-started crops, 'days to maturity' are from when healthy six week old plants are tucked into warm soil after nighttime temps are reliably above 50 degrees F.
So let's put our Chicago Brandywines out on May 15th—when we still might need a season-extending device as insurance. (I am an avowed planting coward and would wait until June 1st to put out unprotected plants in that area. I often wait until then to plant in MY area, which is not quite as chill.) Anyway, the earliest we could reasonably expect the first ripe tomato would be around August 15th, and September 1st would not be unusual.
And Brandywine is not the latest-maturing variety. Not by a long shot; some equally-treasured heirlooms are rated at 100 days! Ah, but grow Brandywine and other big tasty heirlooms you should, weedhopper; their size and complex flavors are legendary. But for ripeness by (or yes, before) the 4th of July you need to look to smaller, hardier tomatoes, whose DNA often hails from places like Eastern Europe, where the complete growing season may only be 60 days.
Siberian tomatoes? Absolutely. And tomatoes in the 'sub-Arctic' series, which was developed in chilly Alberta. And other legendary cold-hardy varieties like 'Oregon Spring' from OSU. But don't get hung up on finding these or other specific varieties. Essentially you want tomatoes whose descriptions include words like "early" and "cold hardy" with days to maturity around or under the number 60. And you want to grow several of these varieties, as they're all going to act a little different in the specific Spring weather you'll get.
Now, the big question: Do you HAVE to start your own plants from seed?
The answer: If you want to try for tomatoes in June, yes. You'd start them ten weeks early instead of six; pot them up into progressively bigger containers at least twice during that time so they can develop deep roots; feed them several times while they're still indoors; and keep them under BRIGHT lights. No half-measures here; only strong, sturdy, stocky plants will survive a really early planting. (Read a few of our seed starting articles for the deep details.)
And if you can't do all that, find a source that can supply you with good-sized starts of a few different early varieties as early as possible in the season.
Then follow the same basic plan whether you personally started or bought the plants: Warm the soil in a raised bed by covering it with clear plastic for a week in advance. Harden the plants off by leaving them outside for progressively longer periods of time each day for that week. Then leave the plastic on the bed, cut holes in it, and plant the tomatoes deeply, just as we always instruct. (See this previous Question of the Week for details.)
Then provide some sort of 'season-extension' protection. Row covers on hoops or other types of insulated tunnels will gain you an extra week or two--especially if you're not really pushing it and/or the weather leans your way. But most of the people who win 'first tomato' contests in the North protect their plants with individual devices that look like upside-down plastic teepees composed of a series of hollow tubes arranged in a circle. You fill the tubes with water; the water heats up during the day and radiates heat back to the plants at night. The originals were called "Walls o' Water", and many variations are now available.
The tops of these devices are always open so the plants can't overheat on a sunny day. And yes, that means that the tops of the plants might get a little chill at night, but studies show that plants react more to cold in the soil than the air. Keeping your soil-warming plastic on the soil keeps the roots warm, and any season extending device will reinforce that bottom heat.
So: How early can people who do all this realistically expect to eat their first ripe tomato?
Master Gardener Andrea Ray Chandler wrote about early tomatoes in the very first issue of ORGANIC GARDENING magazine that I edited—back in 1991; some of our advice comes from that very story. Growing in chilly USDA Zone 5—just like Chicago Jim, who got us started on this topic—Andrea reported that she had picked her first ripe tomato on May 30th of the previous year.
Now, she's a Master Gardener with many years of experience who devotes a lot of time and energy to this and you're not going to match her achievement without at least several years of experimentation and experience, which is why we're talking the 4th of July as a reasonable goal. (And yes, earlier if you are experienced and/or live in a more forgiving clime.)
Promised timing bonus! We didn't have time for this on the show, but I promised I would provide it as an exclusive extra here at Gardens Alive; my 'back of the envelope' calculator for starting your own plants from seed!:
Let's be aggressive and call June 1st Tomato Day One, and say you're in USDA Zone 5 or 6. April + May = the 60 growing days the earliest tomatoes require. Let's say you're putting out six-week old starts. I like to allow two weeks for germination (because it makes the math easy)—that's another 60 days, or all of February (a short month anyway) and March.
So if you start seeds of the right variety on the 1st of February (which is soon; get those seeds in hand!), and do it right you should have nice big plants to put out at the beginning of April, when the odds are mostly good that season-extending devices and some common sense will carry you through chilly nights. (But there's a reason April has been called 'the cruelest month'—so don't put them out in a snowstorm; another week or two indoors is much better than planting during a polar vortex!)
If you're content with shooting for the 4th of July (and I'm with you, not the June Swooners), start on the 1st of March. That's March and April to grow inside, a May 1st planting goal (maybe it won't snow!) and May and June for growing.That 4th of July all-home-grown salad is looking real doable now…..