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When to Plant Squash (Summer) in Hillsborough County, FL

Summer squash includes zucchini, yellow crookneck, and pattypan varieties that are harvested young and tender. They are prolific producers in warm weather.

Hillsborough County, Florida is in USDA Zone 9b. The average last spring frost is January 25 and the first fall frost is December 20, giving you a growing season of approximately 329 days.

At an elevation of 63 feet, Hillsborough County receives approximately 54.4 inches of rainfall annually with predominantly sand soil. Summer highs average 98ยฐF, so Squash (Summer) may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Squash (Summer) will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Squash (Summer) root diseases.

Hillsborough County, FL (Zone 9b) Year-round
329 days
Last Spring Frost January 25
329 growing days
First Fall Frost December 20

Hillsborough County Soil Profile

Soil Type

Sand

Soil pH

4.9-5.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (207 days to spare)
Start indoors: Dec 20 Transplant: Jan 24 🍅 Harvest: Mar 14 – May 16
Recommended (50%) ✓ Fits season (210 days to spare)
Start indoors: Dec 28 Transplant: Feb 1 🍅 Harvest: Mar 22 – May 24
Safe Start (90%) ✓ Fits season (186 days to spare)
Start indoors: Jan 26 Transplant: Mar 2 🍅 Harvest: Apr 20 – Jun 22

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Hillsborough County

How your county's soil matches Squash (Summer)'s growing requirements.

Soil pH

Your soil pH (4.9โ€“5.9) is more acidic than Squash (Summer) prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Hillsborough County warms quickly in spring but drains fast. Squash (Summer) will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Squash (Summer).

Organic Matter

Organic matter is low (1.5%). Add 2-3 inches of compost before planting Squash (Summer).

How to Plant Squash (Summer)

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Succession Planting Squash (Summer)

8
successive plantings in your 329-day season

Sow every 5.1 weeks. Last sowing by Oct 16 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.7″/week
Watering frequency 2-3 times/week
Season total 2,142 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Squash (Summer)

Squash (Summer) needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Squash (Summer) Needs Rainfall You Supplement Action
Jan 4.3" 2.3" 2" ๐Ÿ’ง Light watering
Feb 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
Mar 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Apr 4.3" 2.1" 2.2" ๐Ÿšฟ Regular watering
May 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Jun 4.3" 8.1" 0" โœ… Rainfall sufficient
Jul 4.3" 8" 0" โœ… Rainfall sufficient
Aug 4.3" 8" 0" โœ… Rainfall sufficient
Sep 4.3" 7.7" 0" โœ… Rainfall sufficient
Oct 4.3" 4.5" 0" โœ… Rainfall sufficient
Nov 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Dec 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering

Water needs are for active growing months only (Janโ€“Dec in Hillsborough County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Squash (Summer) Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Squash (Summer) needs ~1,292 GDD — county provides 7,755 GDD Excellent fit

Squash (Summer) Planting Timeline โ€” Hillsborough County, FL

Squash (Summer) Planting Calendar

Activity When Date Range
Start Indoors December 28 Dec 28 โ€“ Jan 11
Transplant Outdoors February 1 Feb 1 โ€“ Feb 15
Direct Sow January 25 Jan 25 โ€“ Feb 15
Harvest March 22 Mar 22 โ€“ May 24

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors Direct Sow
February Transplant Outdoors Direct Sow
March Harvest
April Harvest
May Harvest
June โ€”
July โ€”
August โ€”
September โ€”
October โ€”
November โ€”
December Start Indoors

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

45โ€“65 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 9b

๐Ÿ“† Growing Season

329 days in Hillsborough County

Growing Tips for Squash (Summer) in Hillsborough County

Direct sow Squash (Summer) outdoors after January 25 in Hillsborough County when soil has warmed and frost danger has passed.

Sandy soil in Hillsborough County dries quickly โ€” mulch Squash (Summer) with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 98ยฐF in Hillsborough County, provide afternoon shade for Squash (Summer) and water deeply in the morning.

Your generous 330.0-day season in Hillsborough County allows multiple plantings of Squash (Summer). Sow every 22.0 days for continuous harvest.

Common pests for Squash (Summer) in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow after last frost on mounds. Harvest frequently when fruits are 6-8 inches for best texture. Check plants daily as they grow rapidly in summer heat.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Squash (Summer) in Hillsborough County, FL?

Hillsborough County is in Zone 9b with an average last frost of January 25. Plan your Squash (Summer) planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Hillsborough County, FL?

Hillsborough County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is January 25 and first fall frost is December 20.

๐ŸŒฑ

Plan Your Garden with Confidence

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Hillsborough County, FL. Local conditions may vary. Last updated: April 2026.