Seventy-five days from sowing is the number that sinks a lot of STM 2255 plants before they even flower right—because that count starts at transplant, not at the seed packet’s germination date, and a grower who sows indoors and marks the calendar from there ends up staking a three-foot cage under a vine that has other plans. Indeterminate means it keeps climbing, keeps setting fruit, and keeps needing more room than the seed rack photo ever suggests.
What STM 2255 actually is
STM 2255 grows as an indeterminate vine, meaning it keeps growing, flowering and setting fruit until frost or disease stops it, rather than ripening in one flush and quitting like a determinate variety. That habit decides the whole growing plan: it wants a stake or cage tall enough to hold a plant that will keep climbing past shoulder height, and it wants the spacing to let air move through a plant that will still be leafy in its ninth or tenth week.
The fruit is the reason growers plant it at all. STM 2255 produces large red beefsteak tomatoes with the dense, meaty flesh and low seed count typical of the type, suited to thick slices for sandwiches and burgers rather than to canning whole or drying. Catalogue listings put days to maturity at roughly 72 days, and that figure is counted from the day you transplant a seedling into the garden, not from the day you sow the seed indoors. Confusing the two is the single most common reason a grower feels shortchanged by a maturity date that seemed to promise an earlier harvest. Before choosing among the dozens of entries in most seed catalogs, it helps to see how this variety compares with others in the wider field of tomato varieties, many of which ripen ten to twenty days faster or slower for the same bed space.
What STM 2255 is good for
A beefsteak earns its keep on a cutting board, not in a stockpot. The same dense, low-water flesh already described for this variety is what lets a slice hold its shape and its juice inside a sandwich or under a burger patty: cut it thick, and it stays a distinct layer instead of collapsing into liquid. That is the mechanical reason slicing tomatoes and paste tomatoes are bred for opposite jobs. A paste tomato is bred with less water and more solid pulp so it reduces to sauce in minutes without hours of simmering off excess liquid; push STM 2255 through that same process and you are mostly boiling away water before you get anywhere near a sauce, which is a poor return on a large fruit. Go the other direction and try to can it whole, and the same big, irregular lobes that make an appealing slice make for awkward jars and uneven texture once processed.
What the catalogue description commits to is limited: “beautiful rich red fruit” tells you appearance and color, not taste. No sweetness, acidity, or aromatic character is documented for this variety, and none should be assumed just because it is a beefsteak — plenty of beefsteaks trend mild, others sharp, and this one hasn’t been specified either way. What can be said with more confidence is textural: expect the firm bite and manageable seed pockets typical of the category, which is why it reads better on a plate raw than reduced in a pan.
For the kitchen, treat it as a fresh-eating tomato rather than a preserving one: sandwiches, burgers, thick raw slices with salt, maybe a simple salad if you don’t mind the seed cavities. If a season produces more fruit than can be eaten fresh, that surplus is better roasted or frozen for later cooking than canned as sauce, since the flesh was never bred to concentrate into one.
Where it ripens in time, and where it is a gamble
The arithmetic is simple once you have the two local numbers. Take your area’s frost-free window from NOAA’s climate normals for your nearest reference station, subtract the week or two the soil needs to warm before you transplant, then subtract STM 2255’s 72 days to maturity. What is left is your margin, the days between first ripe fruit and the first fall frost. Under thirty days of margin means a single flush of fruit, and a cool year takes even that.
Where the margin runs out
In Nunavut, using Rankin Inlet as the reference station, plants set out in early July would ripen their first fruit only around mid September, right at the frost line itself: zero days of margin. One wave of fruit is all the season allows, and a cooler-than-average year can erase even that. The bigger problem there is not frost timing at all but total accumulated warmth, which Rankin Inlet does not have enough of in a season regardless of how long the frost-free stretch runs, so a greenhouse or high tunnel is not optional, it is the only way the plant sees fruit at all.
Northwest Territories, at Yellowknife, and Alberta, at Calgary, both land in similar territory: roughly thirty days of margin with plants set out in early June and first fruit expected by mid August. That is enough for a real harvest under glass or plastic, but both stations also fall short on cumulative seasonal heat, which is the reason the verdict there is a greenhouse rather than open ground even though the frost dates alone look almost survivable. Manitoba, at Winnipeg, and Saskatchewan, at Saskatoon, sit a notch better with margins in the mid thirties, close enough that an early-maturing companion variety and a plastic mulch to push soil temperature up can tip a marginal year into a good one.
Where the margin is not the question
Further south the arithmetic stops being the limiting factor entirely. Washington, at Seattle, offers roughly 154 days of margin with transplants going out in mid March to early April and first fruit by mid June. South Carolina, Florida, Texas, Nevada and Louisiana all run margins well past 150 days, with Louisiana’s New Orleans station showing the widest spread at roughly 226 days between first ripe fruit and first frost. In every one of these places the frost table says comfortable, and yet the growing season is not actually one long stretch. That is the subject of the next section.
The two ways a season goes wrong
A long frost-free window is not the same as a good tomato season, and STM 2255’s mid-to-late maturity puts it at real risk from both directions.
Cold that keeps the plant slow, not dead
In the far north the frost dates can look almost workable while the season still fails, because accumulated seasonal warmth, not frost alone, decides whether a plant ever reaches full production. Rankin Inlet’s total heat units for the year fall so far short that even a frost-free stretch long enough on paper cannot ripen the fruit outdoors. Nights that drop below roughly 50°F also stop pollen from setting properly, which quietly kills fruit set well before any actual frost arrives, and a grower who is only watching the calendar for frost dates can miss this entirely.
Heat that shuts pollen down
In the deep south the opposite problem shows up in the middle of summer rather than at the edges of the season. Once daytime temperatures push past roughly 86°F, tomato pollen goes sterile and flowers drop without setting fruit, which is why Charleston, Jacksonville, Houston, Las Vegas and New Orleans gardeners run a spring crop and a separate autumn crop rather than one continuous harvest. For STM 2255, with its 75 to 72 day span to first fruit, this matters more than the cold-side risk almost everywhere the variety is grown at all, because the heat window closes the option of a second sowing unless it goes in early enough to finish before the hot stretch begins. A shorter-season variety planted alongside it, something like the fast-cropping Cherry Bomb cherry tomato, can fill the gap in a garden where STM 2255’s slower timeline leaves too little runway before the heat shuts pollen down.
What it resists, and what it does not
STM 2255 carries a documented high resistance to Fusarium Crown and Root Rot, a soil-borne fungus that otherwise causes wilting and yellowing that climbs up one side of the plant before killing it outright. High resistance means the plant is bred to fend the disease off in the great majority of cases, which is meaningfully different from the intermediate resistance ratings you will see on other varieties, where the plant slows the disease’s progress but can still succumb to it under heavy pressure. If a catalogue lists a variety as intermediate against a disease, do not read that as protection, read it as delay.
Outside of Fusarium crown and root rot, STM 2255’s catalogue listings do not carry resistance codes for the other major tomato diseases: no listed resistance to early blight, late blight, verticillium wilt, or root-knot nematodes. That gap matters in practice more than the one resistance it does have, because verticillium and late blight are common in exactly the humid, warm regions where this variety’s long season gives it the most time in the ground to be exposed to them. A grower in a region with a history of either disease should plan on crop rotation and good airflow rather than count on the plant to shrug it off, since nothing in its catalogue profile suggests it will.
Growing it without the usual mistakes
Because STM 2255 is indeterminate, it needs a support system built for a plant that keeps climbing rather than a cage sized for a compact determinate bush. A single stake driven deep at planting time, or a length of sturdy cattle panel trellis, holds up better over a full season than the flimsy wire cages sold for smaller tomatoes, which tend to topple once a heavy beefsteak plant is loaded with fruit in its later weeks.
Spacing and feeding across a long season
Give plants enough room, generally on the wider end of whatever spacing your seed source recommends, since an indeterminate vine left crowded stays wet longer after rain or irrigation and that dampness is exactly what invites the fungal diseases the plant has no listed resistance to. Keep feeding through the season rather than stopping after the first fruit set, since an indeterminate plant is still building new growth and new flower clusters well into its later months, unlike a determinate variety that can be tapered off once its one flush is underway. Stop nitrogen-heavy feeding once fruit is sizing well, though, or the plant channels energy into leaf growth at the expense of the Beefsteaks you actually want.
The mistake its timing specifically invites is starting too late. With 72 days needed just to reach first ripe fruit, a transplant date pushed back by even a couple of weeks, whether from a late spring or from waiting too long to harden off seedlings, can push the whole harvest into the risky end of the season in any region with a margin under about sixty days. Growers wanting a hedge against that risk sometimes plant a faster variety alongside it, the way a grower comparing timelines might look at the roughly 60-day Nova tomato as a quicker-cropping companion that fills the table while STM 2255 is still weeks from its first fruit.
Common questions
How many days does STM 2255 actually take to ripen?
Catalogue listings put it at roughly 72 days from transplant, not from the day you sow seed indoors. Expect the figure to shift by a week or so either direction depending on how warm and sunny your particular season runs.
Can I grow STM 2255 in a short-season climate with a greenhouse?
Yes, and in places with genuinely short or cool seasons a greenhouse or high tunnel is usually the difference between a real harvest and none at all. It raises both the season length and the accumulated warmth the plant needs, which a frost date alone cannot fix.
Why did my STM 2255 plants stop setting fruit in midsummer?
The most likely cause is heat, not disease or a watering problem. Once daytime temperatures run past roughly 86°F for a stretch, tomato pollen becomes sterile and flowers drop without ever setting fruit, and the plant typically resumes once nights cool down again.
Does STM 2255’s Fusarium resistance mean I don’t need to rotate my tomato bed?
No. High resistance to Fusarium crown and root rot protects against that one disease specifically, and the variety carries no listed resistance to verticillium wilt, blight, or nematodes. Rotating tomatoes out of the same soil for a few years still matters for those threats.