When to plant tomatoes in Hamamatsu: 5 April – 28 August

In Hamamatsu, tomato: sow for seedlings from 22 January to 7 July; plant into a greenhouse from 15 March to 28 August; plant out into open ground from 5 April to 28 August. For plants and seeds, the places nearby include 農家の店ハレとケ (farm shop, 3 km) and ひかり農園 (farm shop, 7 km); addresses and opening hours are below.

Tomato in Hamamatsu: soil, season and weather

In Hamamatsu the soil, not frost, sets the date: the last frost is over around 24 February, but the top 7 cm of soil reaches 15 °C — the minimum on the tomato card — only around 5 April, 40 days later.

Last spring frost	24 February
Top 7 cm of soil at 15 °C	5 April, 40 days after the last frost
Into an unheated greenhouse	15 March – 28 August; March outside: 5.9 °C at night, 15.3 °C by day; card 16–27 °C
First autumn frost	18 December, 257 days after the start
Days in the bed to the first harvest (card)	70
First harvest, if planted in this window	14 June – 6 November
Days left for picking	187
Daylight	10:50 on 12 February, 12:41 on 5 April
Watering outdoors when fruiting (card)	every 3 days; the driest month, December, has 6 rainy days

Tomato in Hamamatsu: care after planting

Planted on 5 April: in the first weeks water every 4 days.

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

5 April — feed: balanced (NPK)
3 May — 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 Hamamatsu during the tomato season

Days average above the tomato card's 16–27 °C in July (29.9 °C), August (31.3 °C) and September (28.2 °C). Months that stay below 16 °C even by day on average: December (12.4 °C). Nights average below 16 °C in April, May and October–December (4–15.4 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
April	19.4	10.4	213	11	13:02
May	23.2	14.6	244	12	13:58
June	26.1	18.8	357	15	14:28
July	29.9	23.3	310	16	14:16
August	31.3	24.4	218	17	13:29
September	28.2	21.3	277	18	12:26
October	23	15.4	227	14	11:21
November	18	9.4	117	9	10:22
December	12.4	4	71	6	9:51

ERA5 2016–2025, Open-Meteo

Tomato in nearby cities

Around Hamamatsu, Tokyo is 1 day earlier and Niigata 30 days later.

City	Distance	Date	Difference
Nagoya	92 km	12 April – 20 August	7 days later
Kyoto	182 km	21 April – 17 August	16 days later
Osaka	204 km	15 April – 27 August	10 days later
Tokyo	209 km	4 April – 24 August	1 day earlier
Okayama	348 km	21 April – 25 August	16 days later
Niigata	376 km	5 May – 30 August	30 days later

Where to buy tomato plants and seeds near Hamamatsu

Buy plants ready to set out from 5 April to 28 August (from 15 March to 28 August for an unheated greenhouse); seed for raising your own is sown from 22 January to 7 July. Within 15 km of Hamamatsu OpenStreetMap lists 5 garden centres, 6 farm-supply shops, 5 markets and 39 farm shops (collected 28 October 2026).

農家の店ハレとケ — farm shop
Mon, Tue, Thu–Sun 10:00–19:00 · 3 km · haretoke.hamazo.tv
ひかり農園 — farm shop
Wed, Sat 13:00–18:00 · 7 km
小澤農園 — garden centre
4 km · ozawa-nouen.co.jp
シード園芸 — garden centre
3 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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