When to plant cucumbers in Portland, Maine: 20 June – 20 August

In Portland, Maine, cucumber: sow for seedlings from 2 May to 23 July; plant into a greenhouse from 30 May to 20 August; plant out into open ground from 20 June to 20 August. For plants and seeds, the places nearby include Harmons Vegetable Stand (farm shop, 12 km); addresses and opening hours are below.

Cucumber in Portland, Maine: soil, season and weather

In Portland, Maine the soil, not frost, sets the date: the last frost is over around 15 April, but the top 7 cm of soil reaches 18 °C — the minimum on the cucumber card — only around 20 June, 66 days later.

Last spring frost	15 April
Top 7 cm of soil at 18 °C	20 June, 66 days after the last frost
Into an unheated greenhouse	30 May – 20 August; May outside: 8.2 °C at night, 17.3 °C by day; card 18–25 °C
First autumn frost	4 November, 137 days after the start
Days in the bed to the first harvest (card)	34
First harvest, if planted in this window	24 July – 23 September
Days left for picking	103
Daylight	14:58 on 23 May, 15:27 on 20 June
Watering outdoors when fruiting (card)	every 2 days; the driest month, September, has 9 rainy days

The same dates in Portland, Maine hold for Bell Pepper, Eggplant, Zucchini, Pumpkin and Watermelon.

Cucumber in Portland, Maine: care after planting

Planted on 20 June: in the first weeks water every 4 days.

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

27 June — feed: nitrogen

Pests and diseases of cucumber 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 Portland, Maine during the cucumber season

No month of the season averages above the cucumber card's 18–35 °C by day; the warmest, July, averages 26.1 °C. Months that stay below 18 °C even by day on average: October (15.6 °C) and November (8.4 °C). Nights average below 18 °C in every month of the season, from 1.2 °C to 17.9 °C.

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
June	22.6	13.9	85	11	15:25
July	26.1	17.9	95	11	15:08
August	25.3	17.2	83	10	14:01
September	21.7	13.7	80	9	12:33
October	15.6	8.1	121	10	11:05
November	8.4	1.2	95	9	9:42

ERA5 2016–2025, Open-Meteo

Cucumber in nearby cities

Around Portland, Maine, Boston is 22 days earlier and Bangor 5 days later.

City	Distance	Date	Difference
Augusta	82 km	22 June – 19 August	2 days later
Concord	115 km	1 June – 16 August	19 days earlier
Manchester (United States)	122 km	30 May – 18 August	21 days earlier
Boston	159 km	29 May – 29 August	22 days earlier
Bangor	179 km	25 June – 19 August	5 days later
Montpelier	196 km	20 June – 2 August	same day

Where to buy cucumber plants and seeds near Portland, Maine

Buy plants ready to set out from 20 June to 20 August (from 30 May to 20 August for an unheated greenhouse); seed for raising your own is sown from 2 May to 23 July. Within 15 km of Portland, Maine OpenStreetMap lists 5 garden centres, 6 markets and 1 farm shop (collected 20 October 2026).

Portland Farmer's Market — market
Wed, Sat 07:00–13:00 · 1 km · portlandmainefarmersmarket.org
Public Market House — market
Monument Square 28, 04101 Portland · 0 km
On The Vine Market Place — market
Route 1 591, 04074 Scarborough · 14 km
Harmons Vegetable Stand — farm shop
Spurwink Road 1, 04074 Scarborough · 12 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