When to Plant Hyacinths in Idaho

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.

Idaho spans USDA hardiness zones 5a, 5b, 6a, 6b, 7a, 7b (with planting data available), so planting dates vary by your location within the state. Click your zone below for the most accurate dates.

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Click your county for exact Hyacinths planting dates based on your local frost dates.

Hover over a county to see details. Click to view planting guide.

Hyacinths Planting Calendar for Idaho

▸ Zone 5a ~166 day growing season · Full guide →

Last frost: April 25 · First frost: October 8 · 166 day season

Activity	When	Date Range
Bloom	August 6	Aug 6 – Sep 3
Fall Sowing	August 27	Aug 27 – Sep 10

▸ Zone 5b ~178 day growing season · Full guide →

Last frost: April 18 · First frost: October 13 · 178 day season

Activity	When	Date Range
Bloom	August 11	Aug 11 – Sep 8
Fall Sowing	September 1	Sep 1 – Sep 15

▸ Zone 6a ~193 day growing season · Full guide →

Last frost: April 10 · First frost: October 20 · 193 day season

Activity	When	Date Range
Bloom	August 25	Aug 25 – Sep 15
Fall Sowing	September 8	Sep 8 – Sep 22

▸ Zone 6b ~205 day growing season · Full guide →

Last frost: April 3 · First frost: October 25 · 205 day season

Activity	When	Date Range
Bloom	August 30	Aug 30 – Sep 20
Fall Sowing	September 13	Sep 13 – Sep 27

▸ Zone 7a ~221 day growing season · Full guide →

Last frost: March 25 · First frost: November 1 · 221 day season

Activity	When	Date Range
Bloom	September 20	Sep 20 – Oct 11
Fall Sowing	September 27	Sep 27 – Oct 11

▸ Zone 7b ~235 day growing season · Full guide →

Last frost: March 18 · First frost: November 8 · 235 day season

Activity	When	Date Range
Bloom	September 27	Sep 27 – Oct 18
Fall Sowing	October 4	Oct 4 – Oct 18

Growing Tips for Idaho

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.

Hyacinths in Other States

Frequently Asked Questions

When should I plant Hyacinths in Idaho?

Planting dates for Hyacinths in Idaho depend on your USDA zone. Idaho spans zones 5a, 5b, 6a, 6b, 7a, 7b. Check the planting calendar above for your specific zone's frost dates and planting windows.

What zone is Idaho for planting?

Idaho contains USDA hardiness zones 5a, 5b, 6a, 6b, 7a, 7b. Your specific zone depends on your location within the state — northern and higher-elevation areas are in colder zones, while southern and coastal areas are warmer.

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