When to plant tomatoes in Missoula: 3 June – 16 June

In Missoula, tomato: sow for seedlings from 22 March to 25 April; plant into a greenhouse from 13 May to 16 June; plant out into open ground from 3 June to 16 June.

Tomato in Missoula: soil, season and weather

In Missoula the soil, not frost, sets the date: the last frost is over around 18 May, but the top 7 cm of soil reaches 15 °C — the minimum on the tomato card — only around 3 June, 16 days later. 125 days separate planting out (3 June) from the first autumn frost (6 October); the card's 70 days to the first harvest leave 55 for picking, so a start 7 weeks late would still fit.

Last spring frost	18 May
Top 7 cm of soil at 15 °C	3 June, 16 days after the last frost
Into an unheated greenhouse	13 May – 16 June; May outside: 4.1 °C at night, 17.4 °C by day; card 16–27 °C
First autumn frost	6 October, 125 days after the start
Days in the bed to the first harvest (card)	70
First harvest, if planted in this window	12 August – 25 August
Days left for picking	55
Daylight	13:24 on 12 April, 15:39 on 3 June
Watering outdoors when fruiting (card)	every 3 days; the driest month, July, has 4 rainy days

Tomato in Missoula: care after planting

Planted on 3 June: in the first weeks water every 4 days.

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

3 June — feed: balanced (NPK)
1 July — 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 Missoula during the tomato season

Days average above the tomato card's 16–27 °C in July (28.3 °C) and August (27.3 °C). Months that stay below 16 °C even by day on average: October (12.6 °C). Nights average below 16 °C in every month of the season, from 1.5 °C to 12.9 °C.

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
June	22.1	8.4	63	10	15:51
July	28.3	12.9	11	4	15:32
August	27.3	12.1	21	4	14:15
September	21.6	7.7	42	6	12:37
October	12.6	1.5	58	11	10:57

ERA5 2016–2025, Open-Meteo

Tomato in nearby cities

Around Missoula, Boise is 37 days earlier and Helena 3 days later.

City	Distance	Date	Difference
Helena	155 km	6 June – 13 June	3 days later
Spokane	271 km	15 May – 25 June	19 days earlier
Boise	400 km	27 April – 7 July	37 days earlier
Idaho Falls	406 km	18 May – 24 June	16 days earlier
Billings	441 km	11 May – 24 June	23 days earlier
Calgary	465 km	3 June – 11 June	same day

Where to buy tomato plants and seeds near Missoula

Buy plants ready to set out from 3 June to 16 June (from 13 May to 16 June for an unheated greenhouse); seed for raising your own is sown from 22 March to 25 April. Within 15 km of Missoula OpenStreetMap lists 3 garden centres, 1 farm-supply shop, 2 plant nurseries, 2 markets and 6 farm shops (collected 28 October 2026).

Warden's Market — market
North Higgins Avenue 451, 59802 Missoula · 3 km
Outside In Garden & Greenhouse — garden centre
3 km
Walmart Garden Center — garden centre
2 km
Clean Green-Lawn Tree — garden centre
8 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.

Questions