When to plant zucchini in Harrisburg: 25 May – 25 August

In Harrisburg, zucchini: sow for seedlings from 13 April to 4 August; plant into a greenhouse from 4 May to 25 August; plant out into open ground from 25 May to 25 August. For plants and seeds, the places nearby include Paulus Farm Market (farm shop, 13 km) and Within You Farm (farm shop, 15 km); addresses and opening hours are below.

Zucchini in Harrisburg: soil, season and weather

In Harrisburg the soil, not frost, sets the date: the last frost is over around 10 April, but the top 7 cm of soil reaches 18 °C — the minimum on the zucchini card — only around 25 May, 45 days later.

Last spring frost	10 April
Top 7 cm of soil at 18 °C	25 May, 45 days after the last frost
First autumn frost	11 November, 170 days after the start
Days in the bed to the first harvest (card)	36
First harvest, if planted in this window	30 June – 30 September
Days left for picking	134
Daylight	14:01 on 4 May, 14:41 on 25 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, November, has 7 rainy days

The same dates in Harrisburg hold for Cucumber, Bell Pepper, Eggplant, Pumpkin and Watermelon.

Zucchini in Harrisburg: care after planting

Planted on 25 May: in the first weeks water every 4 days.

Pests and diseases of zucchini to watch for:

Weather in Harrisburg during the zucchini season

About 714 mm of rain falls in the season; November is the driest month (70 mm) and July the wettest (126 mm).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	22.2	11.4	121	15	14:24
June	27.6	16.5	97	13	15:02
July	31	20.1	126	13	14:47
August	29	19	110	12	13:48
September	25.4	15.7	111	10	12:30
October	19.3	9.7	79	9	11:11
November	11.8	2.9	70	7	9:58

ERA5 2016–2025, Open-Meteo

Zucchini in nearby cities

All the nearest cities on our list plant zucchini earlier than Harrisburg; the closest date is in Hagerstown, 2 days earlier.

City	Distance	Date	Difference
Hagerstown	103 km	23 May – 25 August	2 days earlier
Baltimore	111 km	5 May – 5 September	20 days earlier
Allentown	124 km	23 May – 17 August	2 days earlier
Annapolis	148 km	8 May – 2 September	17 days earlier
Philadelphia	150 km	14 May – 25 August	11 days earlier
Washington, D.C.	152 km	4 May – 30 August	21 days earlier

Where to buy zucchini plants and seeds near Harrisburg

Buy plants ready to set out from 25 May to 25 August (from 4 May to 25 August for an unheated greenhouse); seed for raising your own is sown from 13 April to 4 August. Within 15 km of Harrisburg OpenStreetMap lists 4 garden centres, 4 markets and 3 farm shops (collected 28 October 2026).

Paulus Farm Market — farm shop
South York Street 1216, 17050 Mechanicsburg · 13 km
Within You Farm — farm shop
Fisher Road 1849, 17055 Mechanicsburg · 15 km
Broad Street Market — market
1 km · broadstreetmarket.org
Brick Building — market
1 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