Days to maturity

robinatsia · March 21, 2018

I have to say that I am a bit confused regarding the term DTM.
For example, the Russian 'Pokoritel severa F1' by description has from germination to technical ripeness only 78...87 days and the Estonian 'Terma' - 90...95. How does this translate into DTM, which, if I am correct, means days to maturity from transplanting? For 'Black Cherry', the DTM is 65 or somewhat more - as I have read. Is there any standard or something, on which the DTM is calculated?
In general, we transplant 6...8 six weeks old plants here in Estonia; in case of early varieties it means that the very first flowers are about to open or already just opened.

AlittleSalt · March 21, 2018

Yes, DTM means Days To Maturity. What I have seen is that DTM is more of an educated guess depending on where and how you garden. 55-70 DTM is an earlier producer. A lot of cherry tomatoes fit in this range. I looked up the yearly weather data for Estonia and it says that "The average temperature in July, which is considered the warmest month of the year, is 16.4 °C (61.5 °F)." https://www.google.com/search?ei=zuK....0.YSo521FkwF4

Do you grow in a hothouse/greenhouse or something like that?

MrBig46 · March 21, 2018

As far as I know, DTM are days calculated from the opening of the flower (pollination) to the maturity of the fruit. This is the indicative data used to compare varieties.
Vladimír

sjamesNorway · March 21, 2018

DTM varies relative to local conditions, and usually is calculated from final transplant to first mature fruit. (Some calculate DTM from germination. I sow 2 months before final transplant, so DTM from germination would be about 8 weeks longer.) DTM is useful only as an indication of whether you can expect a variety to be early, mid or late season. I try to find reports of DTM from growers who have similar conditions to mine, either growing in a greenhouse or a decidedly cool outdoor summer. I've seen reports of Indian Stripe having a dtm of 80 days. Last year Indian Stripe Potato Leaf matured after 55 days in my greenhouse, so you won't know for sure until you've grown it yourself.

Steve

brownrexx · March 21, 2018

I don't think that DTM has a firm technical definition.

It seems to be generally accepted as the number of days from transplant to bearing the first mature fruit but is more helpful as a comparison between varieties. In other words it gives an idea of which ones produce earlier than others rather than a firm date as to when to expect a harvest.

Last year I transplanted my 6-8 week old Sun Sugar seedlings outside and picked my first 2 tomatoes 56 days later. Sun Sugar has a DTM of 62 days so this was pretty close.

I basically use DTM as a guideline not a firm date to expect tomatoes.

bower · March 21, 2018

Personally I prefer to use days from germination to ripe fruit instead of DTM.

I usually plant at 6 to 8 weeks as well.

The DTM concept does have some merit though, as I discovered last year when the weather turned nasty and I had to hold my seedlings another two weeks before planting. Where transplant = the resources for the plant to grow big enough, you may as well count from that date, if planting off schedule. That is a solid bet for most varieties.

I also think it may have started as a marketing idea. DTM's are slapped onto seedlings for sale, then the buyer knows what to expect from transplant time.

Andrey_BY · March 21, 2018

I agree with bower. A germination time is the best starting point of counting to ripe fruit. We've been never using DTM counting method here neigher in Soviet Union time nor in present days.

brownrexx · March 21, 2018

Tomatoes are not a crop that is direct seeded here but the majority of my veggies are direct seeded so the DTM is useful for them.

Gardeneer · March 22, 2018

In the US DTM means from tranplant ( seedling of about 8 inch tall).
To me it is a rough ball park number. The same variety in different growing conditions/climate may have baried DTM. In cool PNW for emple it will take much longer than in the south like Alabama
From Seed to Ripe Fruit add about 45 days. So if a variety os listed as with DTM =75 , it will take about 120 days from sowing seeds.

MrBig46 · March 22, 2018

An adult plant is the one that begins to blossom. It does not matter its height. That's why DTM counts from that moment.
During a short day, the pre-growing of the seedlings (without illumination) is significantly longer than 45 days.
Vladimír
It does not matter if the pre-cultivation is added or subtracted. I'm satisfied with the system that uses Tania: Early - midseason - late.

March 21, 2018	#1
robinatsia Tomatovillian™ Join Date: Mar 2018 Location: Estonia Posts: 20	Days to maturity I have to say that I am a bit confused regarding the term DTM. For example, the Russian 'Pokoritel severa F1' by description has from germination to technical ripeness only 78...87 days and the Estonian 'Terma' - 90...95. How does this translate into DTM, which, if I am correct, means days to maturity from transplanting? For 'Black Cherry', the DTM is 65 or somewhat more - as I have read. Is there any standard or something, on which the DTM is calculated? In general, we transplant 6...8 six weeks old plants here in Estonia; in case of early varieties it means that the very first flowers are about to open or already just opened.

March 21, 2018	#7
Andrey_BY Tomatovillian™ Join Date: Feb 2006 Location: Minsk, Belarus, Eastern Europe (Zone 4a) Posts: 2,278	I agree with bower. A germination time is the best starting point of counting to ripe fruit. We've been never using DTM counting method here neigher in Soviet Union time nor in present days. __________________ 1 kg=2.2 lb , 1 m=39,37 in , 1 oz=28.35 g , 1 ft=30.48 cm , 1 lb= 0,4536 kg , 1 in=2.54 cm , 1 l = 0.26 gallon , 0 C=32 F Andrey a.k.a. TOMATODOR Last edited by Andrey_BY; March 21, 2018 at 03:40 PM.

March 22, 2018	#9
Gardeneer Tomatovillian™ Join Date: Feb 2015 Location: NC - zone 8a - heat zone 7 Posts: 4,919	In the US DTM means from tranplant ( seedling of about 8 inch tall). To me it is a rough ball park number. The same variety in different growing conditions/climate may have baried DTM. In cool PNW for emple it will take much longer than in the south like Alabama From Seed to Ripe Fruit add about 45 days. So if a variety os listed as with DTM =75 , it will take about 120 days from sowing seeds. __________________ Gardeneer Happy Gardening !

March 22, 2018	#10
MrBig46 Tomatovillian™ Join Date: Feb 2013 Location: Czech republic Posts: 2,541	An adult plant is the one that begins to blossom. It does not matter its height. That's why DTM counts from that moment. During a short day, the pre-growing of the seedlings (without illumination) is significantly longer than 45 days. Vladimír It does not matter if the pre-cultivation is added or subtracted. I'm satisfied with the system that uses Tania: Early - midseason - late. Last edited by MrBig46; March 22, 2018 at 04:06 AM.

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March 21, 2018	#2
AlittleSalt BANNED FOR LIFE Join Date: May 2014 Posts: 13,333	Yes, DTM means Days To Maturity. What I have seen is that DTM is more of an educated guess depending on where and how you garden. 55-70 DTM is an earlier producer. A lot of cherry tomatoes fit in this range. I looked up the yearly weather data for Estonia and it says that "The average temperature in July, which is considered the warmest month of the year, is 16.4 °C (61.5 °F)." https://www.google.com/search?ei=zuK....0.YSo521FkwF4 Do you grow in a hothouse/greenhouse or something like that?

March 21, 2018	#4
sjamesNorway Tomatovillian™ Join Date: Oct 2014 Location: Norway Posts: 1,049	DTM varies relative to local conditions, and usually is calculated from final transplant to first mature fruit. (Some calculate DTM from germination. I sow 2 months before final transplant, so DTM from germination would be about 8 weeks longer.) DTM is useful only as an indication of whether you can expect a variety to be early, mid or late season. I try to find reports of DTM from growers who have similar conditions to mine, either growing in a greenhouse or a decidedly cool outdoor summer. I've seen reports of Indian Stripe having a dtm of 80 days. Last year Indian Stripe Potato Leaf matured after 55 days in my greenhouse, so you won't know for sure until you've grown it yourself. Steve

March 21, 2018	#5
brownrexx Tomatovillian™ Join Date: Feb 2016 Location: Southeastern PA Posts: 1,420	I don't think that DTM has a firm technical definition. It seems to be generally accepted as the number of days from transplant to bearing the first mature fruit but is more helpful as a comparison between varieties. In other words it gives an idea of which ones produce earlier than others rather than a firm date as to when to expect a harvest. Last year I transplanted my 6-8 week old Sun Sugar seedlings outside and picked my first 2 tomatoes 56 days later. Sun Sugar has a DTM of 62 days so this was pretty close. I basically use DTM as a guideline not a firm date to expect tomatoes.

March 21, 2018	#6
bower Tomatovillian™ Join Date: Feb 2012 Location: Newfoundland, Canada Posts: 6,794	Personally I prefer to use days from germination to ripe fruit instead of DTM. I usually plant at 6 to 8 weeks as well. The DTM concept does have some merit though, as I discovered last year when the weather turned nasty and I had to hold my seedlings another two weeks before planting. Where transplant = the resources for the plant to grow big enough, you may as well count from that date, if planting off schedule. That is a solid bet for most varieties. I also think it may have started as a marketing idea. DTM's are slapped onto seedlings for sale, then the buyer knows what to expect from transplant time.