Louisiana planting calendar

When to plant rosemary in Louisiana — sow, transplant & harvest dates

Louisiana is mostly USDA zone 9a (range 8a-9b). Dates below are derived from rosemary's frost tolerance and Louisiana's frost window — not generic national averages.

Rosemary planting timetable for Louisiana

Stage	When in Louisiana	Anchor
Start seeds indoors (spring crop)	early January (January 4)	10 weeks before the last frost (mid-March)
Transplant outside (spring crop)	late March (March 29)	14 days after the last frost (mid-March)
Spring-crop harvest	late June onward, before peak summer heat	90-day crop — finishes before mid-summer
Plant the fall crop	early August (August 3) — once the worst heat breaks	~104 days before the first fall frost (mid-November)
Fall-crop harvest	early November into early winter	90-day crop — often the more productive of the two

Dates are state-wide averages for the dominant zone. Local microclimates — elevation, urban heat, coastal moderation — can shift the window by 1-2 weeks. Use the frost-date calculator for a date tuned to your town.

Why Louisiana's climate shifts the rosemary dates

Louisiana's long hot summer shuts down fruit set, so locals run two short crops — a spring planting and a fall planting — around a deliberate mid-summer pause, instead of one long northern-style season. Louisiana is hot, humid, and subtropical with a very long season. Drainage, heat, and humidity drive plant choice far more than cold.

Start seeds indoors 10–12 weeks before the last frost; germination is slow and erratic (14–21 days at 18–21 °C / 65–70 °F) with low viability, so propagation by stem cuttings is preferred by most Extension services. Transplant outdoors after the last frost once soil has warmed — rosemary is perennial only in USDA zones 7–10 (established plants survive to about −12 °C / 10 °F); in zones 6 and colder treat as a tender annual or overwinter potted plants indoors before the first autumn frost. Tip harvests of stem ends begin around 80–100 days from transplant.

Frost-risk note

A light frost in the northern parishes near Shreveport (zone 8a) can clip an early spring planting; the bigger risk is mid-summer heat sterilising flowers.

Regional variation within Louisiana

the Gulf Coast and New Orleans (zone 9b) can start the spring crop weeks earlier and may garden almost year-round; the northern parishes near Shreveport (zone 8a) runs a shorter, more northern-style single season.

New Orleans — USDA zone 9b
Baton Rouge — USDA zone 9a
Shreveport — USDA zone 8b
Lafayette — USDA zone 9a

What else to plant in Louisiana around then

Pair the spring slot with other heat-lovers (peppers, squash, beans); use the cool October–February window for greens and brassicas.

Quick-grow guide

Sun: Full sun — 6+ hours direct.
Soil temperature for germination: 18–21 °C (65–70 °F).
Spacing: 18–36 inches (45–90 cm) between plants.
Days to harvest: ~90 days from planting out.

Frequently asked questions

When is the best time to plant rosemary in Louisiana?

In Louisiana (mostly USDA zone 9a), sow rosemary indoors around early January, set the spring crop out late March, harvest before peak summer heat, then plant a second crop early August for an autumn harvest. Avoid mid-summer. Rosemary are half-hardy — young plants shrug off a light frost but not a hard freeze, so sowing can start a couple of weeks before the last spring frost.

What USDA zone is Louisiana?

Most of Louisiana sits in USDA hardiness zone 9a, with the state spanning roughly 8a-9b from the northern parishes near Shreveport (zone 8a) to the Gulf Coast and New Orleans (zone 9b). The last spring frost averages mid-March and the first fall frost mid-November.

Can you grow rosemary in Louisiana?

Yes. Louisiana's dominant zone 9a supports rosemary — the key is timing. Rosemary are half-hardy — young plants shrug off a light frost but not a hard freeze, so sowing can start a couple of weeks before the last spring frost.

Does the planting date change across Louisiana?

What else can I plant in Louisiana around the same time?

Pair the spring slot with other heat-lovers (peppers, squash, beans); use the cool October–February window for greens and brassicas.

Source and methodology

State zone spans from the USDA Plant Hardiness Zone Map (2023); frost-date averages from NOAA Climate Data Online. Hot-state two-season timing cross-checked against the UF/IFAS Florida Gardening Calendar and the University of Arizona Cooperative Extension planting calendar. Curated by the Growli editorial team.