Borage is the blue-flowered bee magnet of the herb garden: its star-shaped flowers are edible, taste faintly of cucumber, and draw pollinators to every bed nearby. It is also one of the easiest herbs to grow in Zone 12 — fast, generous and self-seeding — though its prickly leaves and sprawling habit mean you should give it room and handle it with care.
Like every crop in the tropics, borage rewards gardeners who work with Zone 12's seasons — the cooler, drier months and the hot, wet months — rather than against them. The planting calendar hub gives the Zone 12 picture month by month, and our guide to when to plant borage in Zone 11 shows how the timing shifts in a cooler zone.
Zone 12 at a glance
USDA Zone 12 covers the warmest, most tropical parts of the United States — Hawaii, Puerto Rico, Guam and the U.S. Virgin Islands. Winters are warm, with average winter lows of 50 to 60°F, and the growing season never really ends.
Zone 12 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 12 guidance |
|---|---|
| Average winter low | 50 to 60°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 | 50–60 days |
| Sowing | direct sow |
| Sun | full sun |
| Soil pH | 6.0–7.0 |
| Spacing | 12–18 inches |
| Water needs | moderate |
| Cold tolerance | hardy |
When to plant borage in Zone 12
Plant borage in Zone 12 in the cool, dry season, from late autumn into winter, when the air is drier and the flowers last longest. Because Zone 12 is frost-free, with winter lows of 50 to 60°F, there is no frost date to wait for — borage will grow in any warm month, but the cool season gives the best flowering and the least disease. Seed germinates in 7–14 days and plants reach harvest size in 50–60 days, so it is one of the fastest herbs you can grow. Check your local extension service for the best local planting window. See the Zone 12 October planting guide for what else to plant that month.
Starting borage in Zone 12
Direct sow borage where it is to grow, since it dislikes transplanting. Sow seed in place, cover lightly, and thin seedlings to 12–18 inches apart — plants grow large and sprawling, so do not crowd them. Germination takes 7–14 days. Once you have grown borage once, it will self-seed freely, and you will rarely need to sow it again; pull up seedlings where you do not want them and let a few grow where you do. The seed starting calculator can help you time your sowing.
Soil, spacing, sun and water
Borage needs full sun and ordinary, well-drained soil with a pH of 6.0–7.0. It is not fussy about fertility — too much fertiliser makes soft, sprawling growth — and it tolerates poor, dry soil better than most herbs. Water needs are moderate: water young plants until established, then water in dry spells. In Zone 12's wet season, good drainage and air circulation matter more than feeding, since damp, crowded plants are prone to mildew.
Companion planting
Good companions for borage include tomatoes, peppers, marigolds and cabbage. It is one of the best companion plants there is: its flowers attract bees and hoverflies, which pollinate your vegetables, and it is traditionally planted with strawberries and tomatoes. Let a few plants self-seed at the corners of beds, where they can do their work without crowding crops. The companion planting finder can suggest combinations for your whole bed.
Pests and problems
The common pests to watch for with borage are aphids, slugs and cutworms. Aphids may cluster on young stems — wash them off with water. Slugs nibble young plants in wet weather, so keep mulch away from stems. Cutworms can sever young seedlings at soil level; a cardboard collar around new plants helps. Borage is otherwise very tough in Zone 12, and its hairy leaves put off most chewing pests on their own.
Harvest and storage
Harvest borage 50–60 days after sowing. Pick young leaves for cooking — they are best young, before the hairs get coarse — and pick flowers as they open, for salads, drinks and cake decorations. The flowers are the real prize: pick them in the morning, use them fresh, and freeze them in ice cubes for summer drinks. Let a few plants go to seed so the patch renews itself, and deadhead the rest to keep flowers coming.
Borage as a bee plant in Zone 12
Borage is famous among beekeepers because its flowers refill with nectar every few minutes, making it one of the richest nectar plants you can grow. In Zone 12, where pollinators work year-round, a patch of borage keeps bees and hoverflies visiting your garden through the cool season, which improves fruit set on tomatoes, cucumbers, squash and fruit trees.
Plant borage near — but not in — your vegetable beds, so its sprawling growth does not shade crops. A few plants at the corners of the garden, allowed to self-seed, will keep the bees coming year after year with almost no work from you.
For a related crop, see our guide to when to plant fennel in Zone 12.
Frequently asked questions
When should I plant borage in Zone 12?
Plant in the cool, dry season, from late autumn into winter, for the best flowering. Seed germinates in 7–14 days and plants reach harvest size in 50–60 days.
Is borage perennial in Zone 12?
Borage is an annual, but it self-seeds so freely in Zone 12 that it behaves like a perennial — let a few plants go to seed and new seedlings will appear on their own.
Can you eat borage flowers?
Yes — the blue star-shaped flowers are edible, taste faintly of cucumber, and are lovely in salads, drinks and as cake decorations. Pick them fresh in the morning.
Why is my borage so prickly?
Borage leaves and stems are covered in fine hairs that feel prickly, especially on older leaves. Pick young leaves for cooking and wear gloves when handling large plants.