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When to plant Hyacinths in Johnson County, AR

Spring Hyacinths in Johnson County goes in mid-spring–late spring, once nighttime temps stop dipping near freezing. A second sowing from October 6 to October 20 extends the harvest into fall.

When to Plant Hyacinths in Johnson County, AR

Johnson County, Arkansas Zone 8a July

Your July gardening checklist

July is a pivotal month for Johnson County, Arkansas gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost March 26
Avg. first frost November 3
Soil temp (4") 83°F
Watering Low
Pest pressure High
Daylight 14.2 hrs

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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.

Johnson County, Arkansas is in USDA Zone 8a. The average last spring frost is March 26 and the first fall frost is November 3, giving you a growing season of approximately 222 days.

At an elevation of 1,347 feet, Johnson County receives approximately 49.7 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
Johnson County, AR (Zone 8a) Long season
222 days
Last Spring Frost March 26
222 growing days
First Fall Frost November 3

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7

Drainage

Well Drained

Hyacinths Planting Risk Windows

Early Start (70% safe) ✓ Fits season (207 days to spare)
Transplant: Mar 21 🌸 Bloom: Mar 14 – Apr 4
Recommended (50%) ✓ Fits season (208 days to spare)
Transplant: Mar 26 🌸 Bloom: Mar 19 – Apr 9
Safe Start (90%) ✓ Fits season (215 days to spare)
Transplant: Apr 9 🌸 Bloom: Apr 2 – Apr 23

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 Johnson County

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

Soil pH

Your soil pH (5.3–7.0) overlaps with Hyacinths's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Hyacinths.

How to Plant Hyacinths

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

Fall planting: Sow 4 weeks before your first frost date for a fall harvest.

Succession Planting Hyacinths

19
successive plantings in your 222-day season

Sow every 1.6 weeks. Last sowing by Oct 06 to harvest before frost.

For a dedicated fall crop, sow by Oct 06.

Hyacinths Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/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 3.8" 0" ❄️ Dormant
Feb 3.8" 0" ❄️ Dormant
Mar 2.2" 4.7" 0" ✅ Rainfall sufficient
Apr 2.2" 3.6" 0" ✅ Rainfall sufficient
May 2.2" 4.1" 0" ✅ Rainfall sufficient
Jun 2.2" 5" 0" ✅ Rainfall sufficient
Jul 2.2" 4.6" 0" ✅ Rainfall sufficient
Aug 2.2" 4.3" 0" ✅ Rainfall sufficient
Sep 2.2" 4.1" 0" ✅ Rainfall sufficient
Oct 2.2" 3.7" 0" ✅ Rainfall sufficient
Nov 2.2" 4.2" 0" ✅ Rainfall sufficient
Dec 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Johnson 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 4,051 GDD Excellent fit

Hyacinths Planting Timeline — Johnson County, AR

Hyacinths Planting Calendar

Activity When Date Range
Bloom September 29 Sep 29 – Oct 20
Fall Sowing October 6 Oct 6 – Oct 20

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

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June
July
August
September 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: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

222 days in Johnson County

Growing Tips for Hyacinths in Johnson County

Direct sow Hyacinths outdoors after March 26 in Johnson County when soil has warmed and frost danger has passed.

Your generous 222.0-day season in Johnson 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 Johnson County, AR?

Johnson County is in Zone 8a with an average last frost of March 26. Plan your Hyacinths planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, AR?

Johnson County, Arkansas is in USDA Hardiness Zone 8a. The average last spring frost is March 26 and first fall frost is November 3.

When should I plant Hyacinths in Johnson County, AR?

In Johnson County, AR, plant Hyacinths after the last frost (around March 26) and before the first frost (around November 3). Best results when soil holds above 50°F.

What growing zone is Johnson County, AR for Hyacinths?

Johnson County sits in USDA Zone 8a. Hyacinths grows reliably in zones 3a through 9b, so it's a good fit here.

Can Hyacinths grow in Johnson County's climate?

Yes — Hyacinths grows well in Johnson County's temperate climate. Johnson County averages a 222-day frost-free season, with last frost around March 26 and first frost around November 3.

🌱

Your Johnson County Garden Planner — Free

A 22-page printable planner built for Johnson County (Zone 8a). 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 Johnson County, AR. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.