When to plant tomatoes in Sendai: 13 May – 3 August

In Sendai, tomato: sow for seedlings from 1 March to 12 June; plant into a greenhouse from 22 April to 3 August; plant out into open ground from 13 May to 3 August. For plants and seeds, the places nearby include marché lien (farm shop, 12 km) and Greenhouse Miyama (garden centre, 12 km); addresses and opening hours are below.

Tomato in Sendai: soil, season and weather

In Sendai the soil, not frost, sets the date: the last frost is over around 31 March, but the top 7 cm of soil reaches 15 °C — the minimum on the tomato card — only around 13 May, 43 days later.

Last spring frost	31 March
Top 7 cm of soil at 15 °C	13 May, 43 days after the last frost
Into an unheated greenhouse	22 April – 3 August; April outside: 5.9 °C at night, 15 °C by day; card 16–27 °C
First autumn frost	23 November, 194 days after the start
Days in the bed to the first harvest (card)	70
First harvest, if planted in this window	22 July – 12 October
Days left for picking	124
Daylight	12:12 on 22 March, 14:10 on 13 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, November, has 9 rainy days

Tomato in Sendai: care after planting

Planted on 13 May: in the first weeks water every 4 days.

Feeding, by the card’s schedule from that day:

13 May — feed: balanced (NPK)
10 June — feed: nitrogen

Pests and diseases of tomato to watch for:

Dates count from the first planting day of the window above; a later planting moves them by as many days.

Weather in Sendai during the tomato season

Days average above the tomato card's 16–27 °C in August (27.9 °C). Months that stay below 16 °C even by day on average: November (12.6 °C). Nights average below 16 °C in May, June and October, November (5–15.6 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	20.1	11.1	129	13	14:14
June	23.1	15.6	151	15	14:49
July	26.7	20.1	214	20	14:35
August	27.9	21.2	241	20	13:41
September	24	17.5	201	18	12:28
October	18.1	10.9	163	12	11:15
November	12.6	5	61	9	10:07

ERA5 2016–2025, Open-Meteo

Tomato in nearby cities

Around Sendai, Tokyo is 39 days earlier and Sapporo 48 days later.

City	Distance	Date	Difference
Niigata	165 km	5 May – 30 August	8 days earlier
Tokyo	305 km	4 April – 24 August	39 days earlier
Hamamatsu	485 km	5 April – 28 August	38 days earlier
Nagoya	493 km	12 April – 20 August	31 days earlier
Sapporo	534 km	30 June – 8 August	48 days later
Kyoto	582 km	21 April – 17 August	22 days earlier

Where to buy tomato plants and seeds near Sendai

Buy plants ready to set out from 13 May to 3 August (from 22 April to 3 August for an unheated greenhouse); seed for raising your own is sown from 1 March to 12 June. Within 15 km of Sendai OpenStreetMap lists 2 garden centres, 1 farm-supply shop, 4 markets and 2 farm shops (collected 28 October 2026).

Greenhouse Miyama — garden centre
Mon–Sun 09:00–17:30 · 12 km
Yuriage Minato Asaichi — market
Mon–Sun 06:00–13:00 · 13 km · yuriageasaichi.jp
marché lien — farm shop
Mon–Sat 10:00–18:00; Sun, public holidays 09:00–18:00 · 12 km
ガーデン・ガーデン — garden centre
9 km

Each window starts on the Greenly calendar date and ends on the last day that still leaves the crop’s days to harvest (from its card) before the average first autumn frost, plus six weeks of picking for crops harvested over weeks (tomatoes, peppers, aubergines, cucumbers, courgettes, pumpkins, watermelons, beans) — our rule; earlier in the window is safer.

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