Brief example of how "meaningless" DTM info can be

[ContainerTed]

Craig, I agree with the pots being warmer early on. In my case, I think the shade that I must endure slows things and may balance out. Anyhow, this year is the best yet.

I'm also doing an experiment on how much direct sunlight affects the plants. Nothing real scientific, but had the opportunity to conduct a comparison.

I have two each of rugose leaf Golden Dwarf Champion, a regular leaf Mini Gold, and a potato leaf Stump OTW. One of each is in my area that gets "Shade - Sun - Shade - Sun" each day. The others get "Shade-Sun". The first group gets about 8 hours of total direct sunlight with a three hour break in the middle. The second group gets direct sunlight beginning at 10 AM and that continues until sunset - about 10-11 hours with no break.

So far, it seems like the first group has more bloom sets in this 90+ heat. The second group fattens up set tomatoes faster than the shade group. No hard data here, but my gut tells me that the toms with more shade are less stressed. The idea for this comparison came from last year when I kept Siberian and Sub-Arctic Plenty going in the "Hot-lanta" drought period by utilizing shade and giving the plants a "cool drink" just before the direct sun got to them. I'm convinced that kept the roots from cooking.

We'll see if production and plant heights, etc bear out any other data that might be significant. Right now, though, it really looks like shade has a definite use in this heat. My only concern with my shade is whether or not the plants can get enough photosynthesis accomplished to give full flavored toms.

Ted

[kygreg]

nctomatoman - that's good information to know and interesting.

[eyolf]

RE: the DTM thing:

I have been a fan of tracking growing degree days for several years now; While I cant control the weather, it is interesting to compare varieties from year to year, and make some educated guesses as to what might do well for me here in MN. It has been cold this year, and the only plants actually having any tomatoes set are Kotlas, Melfort, and (no surprise) one I've been fooling around with that I call Heshpole.

Thanks to Darryl Jones for original seed that apparently contained genes for blossoms that appear fairly early, but more importantly, pollinate and stay on the plants during cool night conditions. IMO, those characteristics are more indicative of earliness than speed of ripening. At least in marginal zones like mine.

But, back to GDD. I have found that most varieties will yield ripe fruit within less than 5% variation in the number of GDD from year to year. While DTM is of some use as a general comparator it is not so good to decide fitness for a particular zone. GDD would be nearly universal. I expect about 975 GDD this year with such a slow start, but I could be below that.

Of course, the entrenched garden industry probably has no interest in making any changes, and there is almost no info available regarding GDD requirements of most home-garden crops/varieties. And the truth is some of today's gardeners won't maintain an interest in their gardens over the entire summer...how could you expect them to choose varieties based on performance when they really don't expect any?

[nctomatoman]

Great post, and thanks for "planting the seed" for consideration of degree days as an indicator - makes perfect sense!

You should try Kimberly as a comparator to Kotlas - also early, I find it the best tasting of the earlies.

[celticman]

Craig I glad to here the deer did not get all you tomatoes. I have noticed the same thing. We had and especially good weather in june for tomatoes.
Celtic

[eyolf]

Craig: I grew Kimberly from you two years running: 6 each of Kimberly, Kotlas, Stupice, Matina, Concrete Red and Burrwood Prize (J. Smarsz of OZ) and Bloody Butcher from Burpee. All small, early, red potatoe leaf types.

I found that Stupice, Kotlas, and Kimberly all ripened at exactly the same time, and of the three, Kotlas was my fave for flavor. But to be fair, the differences between them was very subtle. Very late in the season, when nights are getting cool and flavor fails, Stupice was better.

But in my climate and to my taste buds, Brandywine rates merely OK. Polish and Pruden's Purple are both better.

[BigdaddyJ]

I haven't tried Kimberly but wanted to add that i had the same results as eyolf re Kotlas vs Stupice. I also give a slight edge to Kotlas for flavor but they ripened within 3 days of each other three years running with seeds started on the same day. And that reminds me to grow Kotlas again next year because my seed is getting old and Kotlas is a vanishing species...

[tjg911]

i could list many different varieties over the years that did not conform from year to year to their dtm. i think this is a rather amazing example and all this is in the same garden not in containers.

as you know, i supplied the prue seeds to the tomato community so i had no one else to ask about their dtm. in the years i grew prue prior to sending out seeds, i found that prue tomato plants put out memorial day (typical for this part of ct) usually produced fruit around aug. 21 to aug 25. one year i did not pick a ripe tomato until labor day weekend but that happened only once!

now that i grow my plants under shop lights (starting seeds on 4/7 to 4/10) and put out 18-20" tall plants with stalks about as thick at the base as my small finger, the dtm has changed dramaticlly. i now pick ripe prue tomatoes around july 18 to july 20 - a full month earlier! i have had some mature around july 6-10 but that is unusual and they usually don't taste good.

dtm is a moving target that depends upon many variables.

tom

[Fert1]

This is the first year I've grown mostly in pots, and I planted early, mid-season, and late-season varieties. They all seem to be coming in right now though. I don't know if it's weather-related or has something to do with being in pots, but I had expected more of a trickle than a downpour. I'm little concerned they will sputter out early, but a few of them are still setting fruit, so I know at least some will continue to bear for a while. DTM seems to be meaningless for me this year.

[Raymondo]

I have a fairly short season (150 days frost free) and find that everything seems to ripen pretty much all at once. I get some coming in early in the season, not necessarily related to DTM, then bang, it's all happening at once, regardless!

[bakersville]

This reminds me of a plant I had few years back that had a dtm of 150 days from transplant.

[PNW_D]

And, for those interested, I finally relocated the GDD calculator - anyone up for an experiment?

Those growing Kimberly - care to check out your GDD for first ripe?

Here's mine: 972 GDD on July 21

and here's the link to the calculator - select (corn and some other crops) - closest to tomatoes (also insert 50 degrees for lower and 85 for upper)

http://ippc2.orst.edu/cgi-bin/ddmodel.pl

[BigdaddyJ]

OK, all my varieties have ripened. The cool, rainy cloudy May and June really delayed ripening compared to year's past. I heard on the Weather Channel that NYC hasn't had a 90F day yet this summer. That's the longest it's ever gone since 1870's! We may have Global Warming but this summer it's been East Coast Cooling! (Now I just jinxed the rest of summer as we'll have 100F days all the way through September...

This Year's DTM'S:

Big Beef 64 Days
Juliet 65
Jetsetter 66
Mountain Spring 87
Momotaro 93
Brandywine Sudduth 94
Brandy Boy 94
Marianna's Peace 94
Gary O'Sena 98
Earl's Faux 98
NAR 100
Chapman 101
KBX 101
KBX (Winter Sown) 103
Brandywine/NAR cross F3 103

What I learned this year:

Gary'O Sena is a great tasting treat!

Be prepared to wait forever if we ever have this cool a summer again. (Man, I was finally used to the HOT ones!)

Don't wait too long to rebar stake your homemade CRW cages before they are flat on the ground and your power is out but you can still keep your drink cool with the hail ice on your deck while you're sawing the tree limbs the 70MPH winds just tore down. (My Texas cages held up just fine BTW)

Savor every season for what it is.

[TZ-OH6]

My DTMs are off this year for some varieties because I planted one area a week before another, from the same set of seedlings. I am getting first ripe fruits on the same dates as other years even though I planted the seeds two weeks later this year... better seedling growth from proper fertilizing this year.