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When to plant Hyacinths in Barnstable County, MA

Plant Hyacinths in Barnstable County after April 18; the prime window is mid-spring–late spring. A second sowing from September 19 to October 3 extends the harvest into fall.

When to Plant Hyacinths in Barnstable County, MA

Barnstable County, Massachusetts Zone 7a August

Your August gardening checklist

If you only do a handful of things in the garden this August, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 18
Avg. first frost October 24
Soil temp (4") 86°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
Looking ahead to September
  • Fall sowing: hyacinths

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Hyacinths (Hyacinthus orientalis) fill the spring garden with an almost overwhelming fragrance — a single cluster of blooms can perfume an entire yard. Dense, upright spikes of waxy florets in shades of purple, pink, blue, white, and red emerge in mid-spring, bridging the gap between the first crocus and the tulip peak. Though bulbs bloom most spectacularly in their first year, established plantings continue to produce graceful, less-dense flower spikes for several years. Deer and rabbits avoid them due to toxic alkaloids.

Barnstable County, Massachusetts is in USDA Zone 7a. The average last spring frost is April 18 and the first fall frost is October 24, giving you a growing season of approximately 189 days.

At an elevation of 518 feet, Barnstable County receives approximately 45.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Hyacinths during the growing season.

Bulb Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting Fragrant
Barnstable County, MA (Zone 7a) Moderate season
189 days
Last Spring Frost April 18
189 growing days
First Fall Frost October 24

Barnstable County Soil Profile

Soil Type

Silt Loam

Soil pH

5-6.4

Drainage

Well Drained

Hyacinths Planting Risk Windows

Early Start (70% safe) ✓ Fits season (176 days to spare)
Transplant: Apr 10 🌸 Bloom: Apr 3 – Apr 24
Recommended (50%) ✓ Fits season (175 days to spare)
Transplant: Apr 18 🌸 Bloom: Apr 11 – May 2
Safe Start (90%) ✓ Fits season (169 days to spare)
Transplant: May 11 🌸 Bloom: May 4 – May 25

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 Barnstable County

How your county's soil matches Hyacinths's growing requirements.

Soil pH

Your soil pH (5.0–6.4) is more acidic than Hyacinths prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Barnstable County is excellent for Hyacinths — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Hyacinths.

How to Plant Hyacinths

6"
Planting Depth
6"
Between Plants
8"
Between Rows

Fall planting: Sow 5 weeks before your first frost date for a fall harvest.

Succession Planting Hyacinths

16
successive plantings in your 189-day season

Sow every 1.6 weeks. Last sowing by Sep 26 to harvest before frost.

For a dedicated fall crop, sow by Sep 19.

Hyacinths Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Hyacinths

Hyacinths needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Hyacinths Needs Rainfall You Supplement Action
Jan 3.2" 0" ❄️ Dormant
Feb 3.1" 0" ❄️ Dormant
Mar 4.2" 0" ❄️ Dormant
Apr 2.2" 3.6" 0" ✅ Rainfall sufficient
May 2.2" 4.7" 0" ✅ Rainfall sufficient
Jun 2.2" 4.7" 0" ✅ Rainfall sufficient
Jul 2.2" 4.9" 0" ✅ Rainfall sufficient
Aug 2.2" 4.2" 0" ✅ Rainfall sufficient
Sep 2.2" 3.4" 0" ✅ Rainfall sufficient
Oct 2.2" 3.3" 0" ✅ Rainfall sufficient
Nov 3.2" 0" ❄️ Dormant
Dec 3" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Barnstable County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Hyacinths 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" — every day above 50°F 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.

Hyacinths needs ~383 GDD — county provides 3,449 GDD Excellent fit

Hyacinths Planting Timeline — Barnstable County, MA

Hyacinths Planting Calendar

Activity When Date Range
Bloom September 12 Sep 12 – Oct 3
Fall Sowing September 19 Sep 19 – Oct 3

Plant 6" deep · 6" apart · Rows 8" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June
July
August
September Fall Sowing Bloom
October Fall Sowing Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

14–28 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7a

📆 Growing Season

189 days in Barnstable County

Growing Tips for Hyacinths in Barnstable County

Direct sow Hyacinths outdoors after April 18 in Barnstable County when soil has warmed and frost danger has passed.

Your generous 189.0-day season in Barnstable County allows multiple plantings of Hyacinths. Sow every 7.0 days for continuous harvest.

General growing tips

Plant bulbs 6 inches deep and 6 inches apart in fall, when soil drops below 60°F. Wear gloves when handling — bulb sap causes contact dermatitis in some people. After bloom, deadhead the spent spike but leave the strap-like foliage until it yellows naturally. For naturalizing, plant at 6–8 inch spacings and allow clumps to mature undisturbed. In zones 7b–9b, treat bulbs as annuals or use pre-chilled stock; performance after year 1 declines in warm-winter zones. For forcing indoors, chill bulbs 10–12 weeks then bring into warmth.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Hyacinths in Barnstable County, MA?

Barnstable County is in Zone 7a with an average last frost of April 18. Plan your Hyacinths planting based on this frost date — see the calendar above for exact timing.

What planting zone is Barnstable County, MA?

Barnstable County, Massachusetts is in USDA Hardiness Zone 7a. The average last spring frost is April 18 and first fall frost is October 24.

When should I plant Hyacinths in Barnstable County, MA?

In Barnstable County, MA, plant Hyacinths after the last frost (around April 18) and before the first frost (around October 24). Best results when soil holds above 50°F.

What growing zone is Barnstable County, MA for Hyacinths?

Barnstable County sits in USDA Zone 7a. Hyacinths grows reliably in zones 3a through 9b, so it's a good fit here.

Can Hyacinths grow in Barnstable County's climate?

Yes — Hyacinths grows well in Barnstable County's temperate climate. Barnstable County averages a 189-day frost-free season, with last frost around April 18 and first frost around October 24.

🌱

Your Barnstable County Garden Planner — Free

A 22-page printable planner built for Barnstable County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Barnstable County, MA. Local conditions may vary. Last updated: August 2026.

Sources & credits

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