Catnip is the herb your cat already knows about: its leaves contain nepetalactone, which sends most cats into a happy frenzy. For gardeners it is also a useful, mint-family perennial with pretty white flowers that bees love — but like all mints, it spreads, so give it a pot or a corner of its own in Zone 11.
Like every crop in the tropics, catnip rewards gardeners who work with Zone 11's seasons — the cooler, drier months and the hot, wet months — rather than against them. The planting calendar hub gives the Zone 11 picture month by month, and our guide to when to plant catnip in Zone 9 shows how the timing shifts in a cooler zone.
Zone 11 at a glance
USDA Zone 11 covers the warmest, most tropical parts of the United States — Hawaii, southern Florida, Puerto Rico and the warmest coastal pockets. Winters are warm, with average winter lows of 40 to 50°F, and the growing season never really ends.
Zone 11 is frost-free year-round: there is no average last spring frost and no average first autumn frost. That means you plant by heat and by the wet and dry seasons, not by frost dates. These are USDA zone averages, not exact figures for any one garden — always check your local extension service and the forecast before planting.
| Detail | Zone 11 guidance |
|---|---|
| Average winter low | 40 to 50°F |
| Average last spring frost | Frost-free (no frost dates) |
| Average first autumn frost | Frost-free (no frost dates) |
| Days to germination | 7–14 days |
| Days to maturity | 70–90 days |
| Sowing | both |
| Sun | full sun |
| Soil pH | 6.0–7.0 |
| Spacing | 12–18 inches |
| Water needs | low |
| Cold tolerance | hardy |
When to plant catnip in Zone 11
Plant catnip in Zone 11 in the cooler months, roughly November through February, so young plants can establish before summer heat and humidity. Catnip is a hardy perennial that persists year-round in frost-free Zone 11, though growth slows in the hottest months. Seeds germinate in 7–14 days and plants mature in 70–90 days. There is no last frost date in Zone 11 — plant by the cool season instead, and check your local extension service for the best local window.
Starting catnip in Zone 11
Start catnip seed indoors in pots or direct-sow into prepared beds — both work. Sow seed about a quarter-inch deep, keep the soil moist for the 7–14 days to germination, and give seedlings strong light. Catnip germinates readily, so thin seedlings to 12–18 inches apart. Nursery plants and divisions are faster: a single plant can be divided in the cool season. Grow catnip in a pot if you do not want it spreading — like mint, it will take over a bed if you let it.
Soil, spacing, sun and water
Catnip needs full sun and well-drained, even poor soil, with a pH of 6.0–7.0. It tolerates dry soil once established and dislikes wet feet, so in Zone 11 dig in coarse grit and avoid low, soggy spots. Water needs are low — water young plants until established, then water only in dry spells. Too much water and too much fertiliser both make soft growth with weak scent. A gravel mulch keeps the crown dry.
Companion planting
Good companions for catnip include tomatoes, peppers, marigolds and cabbage. Catnip is a classic companion for brassicas and roses, and its scent is said to deter aphids and flea beetles from nearby plants. Chives grow on a similar schedule and share a herb bed well — see our guide to when to plant chives in Zone 11. Keep catnip away from plants it can swamp, and away from your best cat-free flower beds — visiting cats will roll in it. The companion planting finder can suggest combinations for your whole bed.
Pests and problems
The common pests to watch for with catnip are aphids, spider mites and whiteflies, though a healthy plant is rarely troubled. Aphids cluster on young tips — wash them off with water. Spider mites appear in hot, dry weather; keep plants watered at the base. In Zone 11, the bigger pest is often the neighbourhood cats, which roll on young plants and flatten them — protect new plantings with a wire cloche until they are established. If you are unsure what is damaging a plant, the pest identifier helper can narrow it down.
Harvest and storage
Harvest catnip 70–90 days after sowing, once plants are well established. Pick leaves and flowering tops as needed, snipping the top few inches, and never take more than a third of the plant at once. The active compound is strongest just before flowering, so harvest heavily then. Catnip dries well: hang small bunches upside down in a shady, airy place, then crumble the dried leaves into a jar for cats or for tea. Cut plants back after flowering to encourage fresh growth.
Catnip for cats and for the garden
Catnip is worth growing even if you have no cat: its white flower spikes feed bees for months, and its scent is said to deter aphids and flea beetles from nearby plants. Dry the leaves for tea, which is mild and calming, or make a simple sachet for a drawer. If you do have a cat, expect it to find the plant long before you do — cats can smell catnip from a surprising distance, and a determined cat will roll on a young plant until it is flat, so protect new plantings until they are big enough to take it.
Frequently asked questions
When should I plant catnip in Zone 11?
Plant in the cooler months, roughly November through February. Seeds germinate in 7–14 days and plants mature in 70–90 days. Catnip is a perennial in frost-free Zone 11.
Will catnip take over my garden?
It can spread like mint if you let it. Grow it in a pot or a contained corner, and pull volunteers while they are small.
Why do cats love catnip?
Its leaves contain nepetalactone, which most cats find irresistible — they roll in it, chew it and get playful. Not all cats react, and kittens usually do not.
How do I protect young catnip from cats?
Cover new plantings with a wire cloche or an upturned basket until they are established. Once plants are big, they can take a certain amount of rolling.