What determines their "season" is their days to maturity, their DTM. DTM is counted from the day they are transplanted to the garden where they will grow, not the day the seed is planted. So no, just starting them early or first won't make them into mid-season plants.

But yes you can back them up a little closer to mid-season by planting them out early under protection. How much it will make them come earlier all depends on the garden environment you can provide. How well you can fool the plant. :)

So for example if it is a 90 day DTM variety and you pre-warm the soil well, transplant it into the warm soil under really good cover and the weather cooperates you might get fruit from it a week or so earlier than you would normally. It will still take the 90 days (DTM is approx.) but it will be 90 days from the early plant out you din in say April rather than 90 days from your normal May.

The risk is the weather may not cooperate and the plant will die or just sit there until its normal planting time before it takes off. Always worth a try though.

Dave

Dave clearly explained DTM. I have to point out to another thing here.

Tomatoes, although have various DTM s, but they are not like beans , lettuce, or squash that come and go fast. In the beans case you plant them in a staggered fashion. But once a tomato plants DTM is reached(first ripe fruit) it will remain productive for a long time. And in your case(Chicago area) they all will last till the first frost.
So, it seems to me, there is no reason in your climate to delay planting tomatoes . Though it can make sense for someone down South in zones 8 or 9.

In a nutshell, what determines whether a variety is early or midseason or late season are the specific GENES in the DNA if each variety.

If you were to look at a single variety listed in the SSE Yearbooks where there are lots o flistings for that variety, you'd see DTM's all over the place since DTM's are also influenced by where a variety is grown, in a geographic sense, how they are grown, as to caging, sprawling, containers,staked, etc,what amendments were used, if s o which ones and howmuch, what the soil is like if grown inground, and what the weather was like in any given season.

Because of all the variables IMO DTM's are really just guesstimates when you see them given in catalogs, for instance. And there are few seed sites where they grow their own plants for seed production, so many of them just use DTM's they see elsewhere. Often DTM averages from SSE Yearbooks, for members, not the public SSE catalog from which anyone can purchase seeds and more.

Carolyn

Thank you for answers!
Based on variety of conditions and variety of tomatoes are there any general trends that are apparent and posted somewhere or it is all on trial and error basis? I mean something to degree caging vs sprawling, containers vs raised bed vs inground, amendments at this time of planting but only when soil is at those temps etc?
Smaller fruit late variety will grow faster than large beefsteak midseason variety?

are there any general trends that are apparent and posted somewhere or it is all on trial and error basis?

Your are seeking perfection in an info data base and it doesn't exist, sorry. It is trial and error in your garden.

As Carolyn said it is basically genetics but all the variables of the growing conditions provided play just as big a role too. So it would be impossible to create a chart for each variety that would hold true everywhere and under all conditions. Best anyone has been able to come up with to sum up all the variables is the DTM for where the plant is grown and it is, as she said, a guesstimate.

Some general suppositions can be made but even they are subject to too many variables to put any money on them.

If "earlier" is the goal then we can make statements based on personal experience and some research studies like

as a general rule caging produces earlier than sprawling simply because there is less pest/disease stress on the plant,

raised beds tend to produce earlier than inground simply because the soil warms faster in raised beds, but that assumes all other factors being equal.

Containers can't be compared to either other method as it is so unique in its methods and requirements.

But even claims such as those all vary widely from location to location and garden to garden.

Bottom line probably the most semi-accurate claim that could be made is that those with shorter growing seasons should focus on early and mid-season varieties rather than late-season ones.

If it was humanly possible to create the perfect growing conditions for a specific variety in 15 different gardens in zone 5 the results would still vary. What would happen in any other zone would vary even more.

Dave

mmm, attempting to delete double posting. Thank you!

This post was edited by lindalana on Sat, Aug 24, 13 at 16:09

I bumped this up to start the discussions again, since this is the time we all draw plans what to plant , when to plant etc.

As mentioned DTM is just a rough estimate. Most seed catalogs list their most optimistic number for some near ideal growing conditions.

But what we can do, is to pick varieties that possibly will do better in our climate. I am , eg, looking for the varieties that (other than shorter DTM) does better in cooler weather(Under 85F. Mostly in 70s). We don't have scorching summer heat around here and night temps NEVER go higher than 55F. So I am looking into those varieties that grow well way up North and in Canada.
Anther factor to consider is the EFFECTIVE growing season length. For this reason, I am not interested in the types that keep growing and growing. Tomato plants, especially, the indeterminants, are very ambitious. They have no clue how long the season will be. Determinants seem to offer a better option for short/cooler growing seasons.

Let's talk about what your choices are for 2014.
I will post my tentative choices in a later posting.

Thought this information might be helpful as well:

Early season = less than 65 days from planting outdoors to harvest (i.e. DTM)
Midseason = between 65 - 80 days
Late season = more than 80 days

I wanted to make sure I classified my tomato harvest ID properly. Evidently above is the general rule when classifying a tomato as a "early, mid or late season" tomato.

smithmal

@ smiyhmal

You definition is pretty much on the target.

There are tomatoes as early 48 DTM and as late as 110 DTM' That is a 60 day span. If you divide it into 3 intervals you will get (
--- less than 68 (Early)
== 68 t0 88 (Mid )
--- greater than 88 (late)

But keep in mind that the listed DTM are ball park numbers . Plus they are based on near ideal climate and growing condition. EG, Bonny's do there test somewhere down in Alabama. So for me here in PNW, probably I have to add 2 more weeks. And that leads the conclusion that I should avoid any and all the Late Season varieties.
Another point, as I have mentioned before is that most tomatoes (especially indets) continue producing once their DTM has reached. So then, your mid season can do what the late season can accomplished. UNLESS there is an specific variety that you GOT TO HAVE IT.

seysonn,

Thanks for your info. I've found various DTM descriptors on different forums. Are your DTM descriptors for categorizing season maturity for tomatoes what vendors and seed exchangers go by? I want to make sure I catagorize my seeds appropriately if/when I start exchanging seeds that I harvest with other members.

Thanks,

smithmal

Just noting that there have been those seasons when my midseason varieties ripened before my earlies and seasons when my late season ones ripened before my midseason ones.

There is no sure way to determine in advance what the weather will be in any season and I'm not the only one who has seen what I described above,

I'll also add that as I got older I pretty much gave up growing earlies since with a week or more time I could have midseason varieties that actually tasted good, which wasn't always true with most of the earlies I grew, with just a few exceptions.

Carolyn

To me, the labels EARLY, MID, LATE are relative and loosely defined and used terms. DTM , on the other hand is more numerical quantification, which is based on statistics and growing conditions. So if you have 150 days of tomato growing season, probably there is no such a thing as LATE season tomato for you.

To say say, Early Season tomatoes do not taste good (or as good) is a poor generalization , in my opinion. Then I personally do not eat plain tomato. Use salt, pepper, oil, vinegar .. or use it in cooking. The third thing is that taste is a subjective thing. I can always talk about how sweet are acidic a tomato is with certainty. But to say that IT DOES NOT TASTE GOOD is often subjective.
jmo

To say say, Early Season tomatoes do not taste good (or as good) is a poor generalization , in my opinion. Then I personally do not eat plain tomato. Use salt, pepper, oil, vinegar .. or use it in cooking. The third thing is that taste is a subjective thing. I can always talk about how sweet are acidic a tomato is with certainty. But to say that IT DOES NOT TASTE GOOD is often subjective.
jmo

&&&&&

Poor generalization?

I was stating my own opinion as many here do for all sorts of subjects, and I did say with some exceptions.My own opinion, to which I'm entitled

Yes, taste is both personal and subjective, has a human genetic factor as well and many many variables are involved as I know I've also stated here many times and have mentioned those variables.

Carolyn

Wil add in it is quite possible to breed an early, mid or late season tomato from any variety by consistently choosing to save seed and replant seed only from the earliest, middle-est, or latest fruit for a few generations.

Seed saving instructions to maintain an existing variety generally say to take some seed from each of the early, mid & late fruits, otherwise you may be accidentally breeding for different characteristics than your original plant.

Wil add in it is quite possible to breed an early, mid or late season tomato from any variety by consistently choosing to save seed and replant seed only from the earliest, middle-est, or latest fruit for a few generations.
%%%%%

Several folks I know have tried that and it doesn't work b'c the seeds are the same as to DTM in the earliest of fruits, mids, and lates. One good example is the variety Joyce's strain of Brandywine when Chuck Wyatt saved seeds only from the early fruits and said he had an early strain of Brandywine, But no one who grew it got the same results. Again, b'c the seeds in the fruits were the same, or pretty much so, some exceptions, but not related to time of ripening.

(Seed saving instructions to maintain an existing variety generally say to take some seed from each of the early, mid & late fruits, otherwise you may be accidentally breeding for different characteristics than your original plant.)

With this I agree. There is genetic heterogeneity within a single variety, so it's important to preserve those traits. And here I'm talking about internode distances, subtle changes in leaf form, etc.

Carolyn

Carolyn