dtm is totally useless

[greggf]

Lots and lots of folks here have mentioned this, but now I've seen it firsthand:

"days to maturity" info is pretty useless.

Beefmaster, a huge 80 day-er, is going to be our first to mature. Next to it are green Early Girls, Good 'n' Earlys, and Early Picks.

Anybody else getting late tomatoes early and earlies late?

[PaulF]

My Early Rouge ripened four tomatoes at 64 days and the other eight on the vine have stayed green and they are now at 78. Since then a trickle of mid to late season tomatoes have been coming in. Most really nice looking but green fruits are waiting for something. I think they know we are going on vacation in a week ( going to try my hand at surf fishing at St. George Island, Florida) and all at once when we aren't home they will get together and decide to get ripe. Thanks tomatoes!

[TomatoDon]

I know. Days to maturity from what day? The only way I see to make it half way reliable is to have it from the day the seeds sprout.

Don

[Razorback04]

Originally Posted by don06

I know. Days to maturity from what day? The only way I see to make it half way reliable is to have it from the day the seeds sprout.

Don

I agree. I've seen several places list DTM as days from setting out. So you're telling me that it doesn't matter if I started them in a greenhouse 3 months ago, and transplanted them into gallon containers? C'mon.

I want to know how many days from the time the seed sprouts until I can get a ripe tomato. Yes, it'll probably be a range, but that's okay with me.

[ddsack]

The other problem is variation in the same variety. I have four Earl's Faux plants. I have picked three tomatoes, two from one plant, one from the 2nd plant. Plants 3 and 4 are way behind and have produced nothing yet. Now, if I were only growing one plant of EF, and it happened to be no. 4, I would say that it was EF was "late" for me, instead of saying that it was early! Go figure!

I normally grow 2 plants of each just to try to avoid dealing with a fluke, but still there is too much variation depending on micro differences in soil fertility and sun availability, even in one person's garden. DTM is barely useful for relative comparisons of varieties, certainly not an actual number of days.

[eyolf]

It has been a warm dry year here in Mn, and we have racked up a goodly number of growing degree days.

I have been using that for comparison rather than DTM.

Go here: http://climate.umn.edu/cropddgen/cropddgen.asp

[NCTIM]

The short answer is I agree DTM's are pretty much useless and yes I have had late ones ripen before early ones. The long answer is....

DTM’s will indeed range even if going by seed sprout. I started a large number of plants this spring for both myself and others. The set out date for mine was earlier than my Uncle’s and his plants were my seedlings. The tomatoes he grew were all earlier than mine and we stay just a few miles apart. When I say all, I mean everyone of them and not by a day or two. His plants had ripe fruit as much as two weeks sooner than mine.

The only thing that’s different for us is the soil. His garden has a lot of sand and my soil has some clay and is much heavier. There is also a slight difference in the amount of full sun he gets.

I also grew plants for a friend at work. He set his out a several weeks after me and a week or so later than my uncle. His DTM's were as much as month behind mine.

Seed sprout date.... Transplant date .... Who knows?


Sometimes I too will have X variety to give a ripe tomato that should be later than Y variety. I have found that when this happens it’s usually only 1 or 2 tomatoes and the larger harvest will still be from the earlier variety.

The early varieties for me seem to be fairly close to projected DTM’s. The rest are always earlier than said DTM.

Tim

[maryinoregon]

I agree that there is very little good in trusting DTM. For instance, I have read Nebraska Wedding is about 90 DTM in my area, but the year I grew it I had ripe ones before most of my cherries. It was insanely productive.

Last year I planted out a month before a gent of my aquaintance planted the starts I gave him. He lives about an hours drive away and at a higher elevation. He planted the starts I gave him in mid-June and had so much ripe fruit while I was barely getting any.

Heat units are probably more accurate, but I try what I want. You need to know what works in your garden and in your microclimates. I surprise people very year. I'm sick of being told that we can only grow extremely early tomatoes in the Pacific Northwest and nothing else. That's a crock!

[Andrey_BY]

I'm very glad you guys start to love Russian days counting system. we are using this DTM system (from germanating day to maturing of the first fruit on a plant) since 1920s in USSR, Bulgary, Hungary, Poland and other Eastern European countries
It works because there is a big difference when you started you seeds 40 days or 70 days before translating seedlings
By the way, our first to ripe tomato variety was a late Orangevyi Gigant (Orange Giant) only because I've started it from seeds in early March instead of other varieties started from mid to the late March

[carolyn137]

Yes, I'm one of the many who in the past has said that DTM's are guesstimates.

Going from when you sow the seeds instead of the conventional definition of from when the seedlings are set out also seems to have some problems, as I see it, b'c of variation in seed viability and also the individual variation in how different folks sow their seeds.

When I refer to tomato varieties in print I just say early, midseason and late season and give a general spread of days for each of those categories.

But the reason I posted was to ask you how you think the different websites, catalogs come up with DTM numbers for varieties?

As I see it there's more than one answer to that question depending on the specific seed source but I think I'll see what some of you say first before I share what I think.

[nctomatoman]

I've also never really paid any attention to DTM. It is all relative to me. A very few small fruited varieties are always first to ripen for me - Kimberly and various cherry tomatoes, Taxi - I just think of them as relatively early. Pretty much all of the rest are lumped in to main season - I am happy when they ripen, but am not at all interested in when that is. With just an incredible number of potential variables, it is hard to pay attention to any sorts of DTM numbers - from seed, from transplant, whatever.

[greggf]

I think seed companies underestimate dtm, oftentimes on purpose, in order to sell us seed.

It's like the "horsepower race" among American cars in the 1960's, where each company mysteriously raised the hp ratings of their engines even when those engines underwent no engineering changes. It was marketing hype to sell cars.

Just now there's a lawnmower engine controversy. Apparently there's a big lawsuit whereby Briggs & Stratton etc. are being sued in a class action lawsuit for overstating engine horsepower claims, all so that marketers can claim that the SodBoy Beaver has more power than the Turkish Grass Queen.

In audio, there was the famous "total harmonic distortion war" of the 1970's, when amplifier manufacturers kept mysteriously lowering the THD figures of their products, sometimes by implementing (sound quality-destroying) excess negative feedback, sometimes by just sending in the marketers to lie about it.

So I think that if Burpee advertises Supersteak as 80 days, then Jung will advertise it as 78, and then next year, Burpee will call it 77 days, and so on, until the class action lawsuits begin.................except that in tomato land, I doubt we can sue!

[Sherry_AK]

A "real" DTM system would be of great benefit to those of us who live in areas with short growing seasons. I understand that there are many, many variables which can affect DTMs. My own personal records have always included the date seeded and the first pick date. I use date seeded rather than germination date, since a given variety can germinate over a period of time. That's just how I do it.

For those of you in warmer climates, it may not matter much if DTM is 77, 82 or 90, because eventually you'll get a ripe tomato. For me, it may be the difference between wasting valuable space and actually getting a tomato.

[Worth1]

It's been about 17,520 days for me and I still havent made it.

Worth

[feldon30]

I think you're thinking ETD.