Tuesday, May 19, 2009

Late Frost and Tender Seedlings


Here I am gardening in hardiness zone 6B. Depending on whom you believe, our average last frost date is either May 5th or May 10th. It's May 19th and there's frost on the grass outside as I type this. I watched my neighbor cover up his tomato seedlings yesterday evening, as I brought my tender heat-loving seedlings indoors for the night. I'm not going to gloat. I hope his seedlings made it. He built some beautiful wooden trellises this year to support his plants. But I am going to take this opportunity to throw my own piece of two-bit advice into the marketplace of gardening ideas.

Don't plant your tomatoes as soon as your last frost date has passed. Don't even plant at a certain amount of time after that date. I'm not saying this simply because of the chance that a late frost could surprise you. The thing I watch for is the day when I can be reasonably certain that overnight temperatures will no longer fall below 50 F (10 C). I know this will come at least a week or two after our average last frost date, and possibly three weeks later or more. I watch the five-day weather forecast, and I won't plant until I see five solid days of overnight temps above 50 degrees. If the predicted overnight low a few days out is exactly 50, I wait. If I see an overnight temperature of 51 or 52, I might plant with a row cover. But mostly I wait.

Why do I use this temperature as a guideline? Because tomatoes are essentially tropical plants. Yes, they've been bred to survive in our northern climes. They'll live through 40 degree nights. But they won't thrive. In my experience, any tomato fruit which has ever been exposed to temperatures below 50 degrees will never develop a good tomato flavor. Even if that fruit is a tiny green bud that has just shed its blossom. And what are we growing our own tomatoes for if not for superb, better-than-candy flavor? Tomatoes need heat and are completely allergic to cold, especially at the beginning of the season. Other gardeners get earlier tomatoes than I do. But the fruits aren't worth a damn, in my opinion.

Even my earliest fruits don't compare to those that mature during the three golden weeks of August. Those fruits probably never know temperatures below 60 or even 65 F. Now those are tomatoes worth eating. They're also worth waiting for. That flavor is the reason why I gave up buying fresh tomatoes at the grocery store, no matter what it says on the sign. "Vine-ripened," "hothouse," - whatever; I don't care. Once you've tasted a real tomato, you won't see the point of eating those red globs of cardboard that are offered for sale 52 weeks out of the year.

All of this goes doubly for pepper plants. They are even more heat-loving than tomatoes. As a rule of thumb, I aim to have my tomatoes in the ground on June 1st, and my peppers in the ground in mid- to late June. That's what works for me in my area anyway. Just don't let your tomato or pepper seedlings get rootbound as you are waiting for the temperature to cooperate. Repot them in larger containers if you need to. Rootbound plants seldom recover to do well in the ground.

I'm sure that seasoned gardeners have their own habits and preferences based on long experience, and I don't intend to start any argument. Direct experience is the best teacher, and it should not be lightly set aside on any authority. My recommendation is offered however to novice gardeners, and I understand that there are many people taking up gardening for the first time this year, due to our lousy economy. It's very easy to get discouraged when our first attempts at any new enterprise fail. So if you're new to gardening, don't necessarily follow what your neighbors are doing. Gardeners can be notoriously optimistic about frosts and planting dates. Everyone is dieing to get that first homegrown tomato. You may do better to wait it out with your heat-loving plants.

Gardening can be an extremely frugal hobby. But it's only frugal if you manage to keep your plants reasonably happy and productive. Losing plants you've grown from seed is absolutely heartbreaking. So take rules of thumb about planting dates with a grain of salt, and beware those late frosts!

11 comments:

Garden Pheenix said...

Yeah I learned this the very hard way. 28 tomato plants wiped out this year :c( I was gutted and have started all over again, which might be completely pointless. Here is hoping September is a hot one!

Kathryn said...

Thank you for sharing. I'm new to gardening, tho i shouldn't be. My parents raised a garden every year.

The charts don't do anything for me. We live in Southern California, but in the mountains (near 7000 Ft elevation). We are zoned by So. Cal & the charts give a last frost date of March, but last year we lost all our apples due to a freeze the end of May. The year before i didn't put out my tomatoes until mid-June, because up to then the temps had been in the 30s.

I haven't had much luck so far. Hoping this year will be better. :)

One Dog said...

Thanks for sharing this. We planted our tomato seeds in the first week of *March*, they got huge, and we were running out of pots to put them in, so we put them in the garden before we should have, the first ones on 5/11. We covered them last Saturday night (5/16-17) for what was, we hope, the last frost. Even so, some of them had some damage although all will survive. I'm sure what you say about them not liking cold at all is correct, and we'll plant seeds about a month later next year.

Meadowlark said...

Sounds like Kathryn and I are in the same boat. And you're too far away to kick in the shins for being a zone 6 :( We're a 4 when we're lucky.

Kate said...

GP, that's tragic. So sorry to hear that. Could you find some seedlings to purchase that suit you? That's what I do when my seeds fail for whatever reason. I always try starting just about everything from seed, but I know I can fall back on seedlings from good local nurseries in a pinch. Don't feel you have to do everything yourself!

Kathryn, sounds like you're in a tough microclimate maybe. I might take drastic measures if I were in your shoes; the row covers and water filled plant warmers. I count myself lucky that all I really need is patience most years. I didn't even know that apples were frost tender. I hope our tree pulls through! It's been a weird and tough spring here too.

One Dog, I hope your plants made it through okay. Gardening is live and learn. I really thought that this year I was showing undue caution. It's been so mild for much of April and early May. Cold snaps can come and bite us though.

Meadowlark, hardiness zone envy is all relative. I tried to ignore the recent posts from the Little Homestead in the City, when they gush about their peaches, strawberries, and blueberries. I think we cooler area gardeners need to remind ourselves about all the insect pests we don't have to deal with by virtue of our long cold winters. But I hear you. I'll try not to rub in my zone 6 status!

Meadowlark said...

Thanks for the thought. Quite honestly, I had never, ever considered the lack of pest point of view.

I think I'll quite my grumbling and head outside to wipe a layer of frost away and do something productive!!! :)

Lily Girl said...

Another thing you guys get are plants that require a freeze in order to produce. There are a number of trees in particular that I can't use in my zone 9/10. And trying to figure out our seasons can be tricky too, since we can't always follow "traditional" guidelines for planting. It's all a trade off. I'm thankful for the chance to garden year-round and have tomatoes nearly as long, but then again I love rain and snow and we don't get much of either!

virginialandscaping said...

Wish I read this a week ago! This was our first year growing tomatoes from seed. It didn't go great to begin with, but we planted last weekend and hoped for the best- and got two nights in the 30s. Oh well, my favorite herb farm was more than happy to sell me starter plants.

Kate said...

ML, no worries. A good grumble now and then is tonic for the soul.

Lilygirl, yes, I do appreciate the many things that grow in my area that need those cold winter days. But like Meadowlark, it's sometimes hard to remember them when warmer zone folks enjoy their berries and peaches so early.

VL, I can relate. I start most things from seed. But every year something fails, and I end up buying seedlings. Nothing wrong with that. In fact, the hit or miss thing keeps it sort of interesting. I'll try posting a rerun of this article a little earlier in the year next year.

Bláithín said...

Excellent post! Sometimes I wonder why I bother starting my tomatoes indoors at all...usually the volunteers that sprout do better than my transplants. I should just direct seed and forget about it :-) And I do hate lugging all those seed trays of seedlings in and out depending on the weather. If I only had a greenhouse.....

Kate said...

Bláithín, thanks. I totally hear you on the hassle of carrying seeds to and fro. I have greenhouse envy too. We're working on a few coldframes for later this year, so maybe next spring we'll have less lugging to do. We have hundreds of volunteer tomatoes too, but since tomatoes cross-pollinate so readily, I always start from seed and kill the volunteers. Sad, but that's the way it goes in the garden sometimes.