When to plant pumpkins in Grand Junction: 6 May – 2 July

In Grand Junction, pumpkin: sow for seedlings from 4 March to 21 May; plant into a greenhouse from 15 April to 2 July; plant out into open ground from 6 May to 2 July. For plants and seeds, the places nearby include West Elk Supply (farm supply, 2 km) and Bookcliff Gardens (garden centre, 3 km); addresses and opening hours are below.

Pumpkin in Grand Junction: soil, season and weather

In Grand Junction the soil, not frost, sets the date: the last frost is over around 18 April, but the top 7 cm of soil reaches 18 °C — the minimum on the pumpkin card — only around 6 May, 18 days later.

Last spring frost	18 April
Top 7 cm of soil at 18 °C	6 May, 18 days after the last frost
First autumn frost	27 October, 174 days after the start
Days in the bed to the first harvest (card)	75
First harvest, if planted in this window	20 July – 15 September
Days left for picking	99
Daylight	12:20 on 25 March, 14:00 on 6 May
Watering outdoors when fruiting (card)	every 5 days; the driest month, June, has 3 rainy days

The same dates in Grand Junction hold for Cucumber, Bell Pepper, Eggplant, Zucchini and Watermelon.

Pumpkin in Grand Junction: care after planting

Planted on 6 May: in the first weeks water every 4 days.

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

27 May — feed: nitrogen

Pests and diseases of pumpkin 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 Grand Junction during the pumpkin season

About 164 mm of rain falls in the season; June is the driest month (13 mm) and October the wettest (54 mm).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	25.4	9.7	30	6	14:18
June	32.8	16.4	13	3	14:54
July	35.1	19.8	15	2	14:40
August	33.3	18.3	24	5	13:44
September	28.9	13.8	28	5	12:29
October	19.6	6.1	54	7	11:14

ERA5 2016–2025, Open-Meteo

Pumpkin in nearby cities

Around Grand Junction, Pueblo is 3 days earlier and Cheyenne 33 days later.

City	Distance	Date	Difference
Denver	316 km	28 May – 20 June	22 days later
Colorado Springs	326 km	6 June – 20 June	31 days later
Salt Lake City	339 km	19 May – 1 July	13 days later
Fort Collins	340 km	7 June – 26 June	32 days later
Pueblo	356 km	3 May – 3 July	3 days earlier
Cheyenne	392 km	8 June – 18 June	33 days later

Where to buy pumpkin plants and seeds near Grand Junction

Buy plants ready to set out from 6 May to 2 July (from 15 April to 2 July for an unheated greenhouse); seed for raising your own is sown from 4 March to 21 May. Within 15 km of Grand Junction OpenStreetMap lists 5 garden centres, 1 farm-supply shop, 1 market and 1 farm shop (collected 28 October 2026).

Bookcliff Gardens — garden centre
26 Road 755, 81506 Grand Junction · 3 km
West Elk Supply — farm supply
Northgate Drive 599, 81505 Grand Junction · 2 km
Jim's Lawnmower Shop — market
Palmer Street 1825, 81503 Grand Junction · 5 km
Willow Bend Farm — farm shop
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