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When Do Tomatoes Bloom? 5 to 7 Weeks After Transplanting

Tomatoes flower about five to seven weeks after transplanting, once night temperatures hold above 55°F. What delays it and what stops fruit setting.

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A tomato flower truss with two open yellow flowers and unopened buds on a hairy green stem
Photo: Beth Fitzpatrick, Pexels License, via Pexels
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Five to seven weeks after transplanting, once nights hold above 55°F. From seed, nine to eleven weeks. But flowering is triggered by the plant reaching size, not by the calendar — which is why a late-planted tomato catches up faster than you would expect.

The timeline

From planting to a tomato you can eat
StageWhen
Transplant outDay 0
First flowers5–7 weeks
Visible green fruitAbout a week after the flower opens
Cherry types ripe20–30 days from set
Beefsteak types ripe50–60 days from set

So open flower to eating is usually six to nine weeks. Petals dropping once a flower has set is normal, not a failure.

Determinate and indeterminate bloom differently

Two habits, two flowering patterns
DeterminateIndeterminate
FloweringOne flush, 1–2 weeksContinuous until frost
HarvestMostly togetherA steady trickle
SuitsSauce, containersFresh eating over a season

Neither is better. If your plant flowered heavily and then stopped, it is probably determinate and doing exactly what it should.

Not flowering at all

A large, lush, dark green plant with no flowers is a nitrogen problem

The plant is being fed to grow leaves and is doing so. A lawn feed or a high-nitrogen general fertilizer will produce this reliably.

Switch to a high-potash feed and stop the nitrogen. It corrects, but not overnight.

The other two causes:

  • Not enough light. Tomatoes want six to eight hours of direct sun
  • Immaturity. A plant that went out late simply has not reached flowering size yet

Flowers that open and drop

Temperature, almost every time:

  • Above ~90°F by day, or ~75°F at night — pollen becomes unviable
  • Below ~55°F at night — the same outcome from the other end
  • Erratic watering and very dry air do it too

In a heatwave there is not much beyond shading the plants and keeping water steady. It resumes when the weather does.

They pollinate themselves

Tomato flowers carry both parts and are self-fertile. Outdoors, wind and passing bees shake the pollen loose without any help.

Under cover it is different — in a greenhouse, polytunnel or still air the pollen can simply sit there. Flicking the flower trusses or tapping the stake every couple of days, in the morning, noticeably improves set.

Common questions

When do tomatoes bloom?

About five to seven weeks after transplanting, which for most gardens means late spring to early summer, once night temperatures are reliably above 55°F. Determinate varieties flower all at once over a week or two; indeterminate ones start at the same point and keep flowering until frost. From seed rather than transplant, count roughly nine to eleven weeks. The plant also needs to reach a certain size first — flowering is triggered by maturity, not only by date.

How long after flowering do tomatoes appear?

A pollinated flower sets a visible green fruit within about a week, and that fruit takes another 20 to 60 days to ripen depending on variety — a cherry tomato ripens in around 20 to 30 days from set, a large beefsteak can take 50 to 60. So from open flower to a tomato you can eat is typically six to nine weeks. The flower itself drops its petals once it has set, which is normal and not a problem.

Why is my tomato plant not flowering?

Too much nitrogen is the commonest cause by a wide margin — the plant grows large, dark green and lush and puts nothing into flowers. A lawn feed or a high-nitrogen general fertilizer will do this. The other causes are not enough light, since tomatoes want six to eight hours of direct sun, and simple immaturity if the plant went out late. Switch to a high-potash feed and be patient.

Why are my tomato flowers falling off without setting fruit?

Temperature, nearly always. Tomato pollen becomes unviable above about 90°F in the day or 75°F at night, and also below about 55°F at night, so flowers open, fail to pollinate and drop. It is extremely common in a heatwave and there is little to do beyond shading the plants and keeping water steady. Inconsistent watering and very dry air cause the same drop.

Do tomato flowers need bees to pollinate them?

No. Tomato flowers are self-fertile and carry both parts, so they pollinate themselves as long as the pollen is shaken loose. Outdoors, wind and visiting bees do that without help. In a greenhouse, a polytunnel or still air the pollen can sit where it is, which is why flicking the flower trusses or tapping the stake every couple of days in the morning noticeably improves set.

Do determinate and indeterminate tomatoes bloom differently?

Yes, and it changes how you handle the plant. A determinate variety sets nearly all its flowers in one flush over a week or two, then stops and ripens everything more or less together, which suits sauce-making and containers. An indeterminate keeps producing flower trusses up the stem until frost kills it, giving a steady trickle instead. Neither is better; they just fit different uses.

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