Nine courgette varieties are sourced for NZ temperate gardens between Kings Seeds NZ and Koanga Institute — a mix of modern F1 hybrids bred for uniform cropping, heirloom open-pollinated types bred for flavour, and one variety that isn't strictly a courgette at all.
The Comparison
| Variety | Supplier | Fruit | Notable for |
|---|---|---|---|
| Black Coral F1 | Kings Seeds NZ | Almost-black, glossy, cylindrical | Open bush habit improves airflow, which reduces powdery mildew risk |
| Gold Rush F1 | Kings Seeds NZ | Golden-yellow, cylindrical | Long harvest window, upright habit for easy picking |
| Black Beauty | Kings Seeds NZ | Dark-green, cylindrical | Highly uniform fruit, open habit for easy harvest |
| Summer Gold | Kings Seeds NZ | Bright yellow, slender | Best picked young; regular picking encourages more fruit to set |
| Cocozelle | Kings Seeds NZ | Pale-green with dark stripes | Classic striped Italian type, best harvested young |
| Cocozelle Bush | Koanga Institute | Green, striped, bush form | Open-pollinated striped type; male flowers also edible |
| Costata Romanesco | Kings Seeds NZ | Grey-green, ribbed | Lower yield than hybrids but stronger flavour; good male-flower producer |
| Long Green Bush Marrow | Koanga Institute | Long, green | Dual-purpose — good picked young as courgette or left to full marrow size |
| Squash Crookneck | Koanga Institute | Yellow, warty when mature | Not a true courgette — a related summer squash, compact bush, very heavy cropper |
The Hybrids
Black Coral F1 and Gold Rush F1 are the two named hybrids in this set, both from Kings Seeds NZ and both bred for an open bush habit that makes picking easier. Black Coral F1's open growth is specifically credited with improving airflow around the plant, which lowers the risk of powdery mildew — a real problem in a crop grown as densely as courgette often is; see Powdery Mildew on NZ Courgettes and Pumpkins if it's already shown up in your garden. Gold Rush F1's main selling point is a long harvest window from a single planting rather than a particular disease trait.
Black Beauty and Summer Gold aren't marketed as F1 hybrids in their own descriptions, but both share the same modern-breeding traits: highly uniform fruit and an open plant habit built for easy harvesting. Summer Gold specifically rewards frequent picking — harvesting young fruit encourages the plant to set more.
The Heirloom, Open-Pollinated Types
Every Koanga Institute variety here — Cocozelle Bush, Long Green Bush Marrow, and Squash Crookneck — is heirloom, open-pollinated seed, the same as Koanga's garlic range (see Best Garlic Varieties for NZ Temperate Gardeners for how that plays out with a different crop). That matters if you want to save your own seed rather than buying fresh each season, something an F1 hybrid can't reliably give you.
Cocozelle Bush is Koanga's own take on the classic striped Italian courgette that Kings Seeds NZ also sells as plain Cocozelle — same striped fruit, different breeding lines. Koanga's version adds one detail the Kings Seeds listing doesn't: the male flowers are edible, a genuine bonus if you cook with squash blossoms.
Costata Romanesco trades yield for flavour — its own description is explicit that the plant produces less fruit than the hybrids here but tastes noticeably better, on a bigger, large-leafed bush. It's also called out as a strong producer of male blossom flowers specifically for cooking, more so than the other varieties in this set.
Long Green Bush Marrow is the one genuinely dual-purpose entry: pick it young and it's a good courgette, but unlike most of the others here it stays tasty left to grow on to full marrow size instead of turning bitter or woody.
The One That Isn't Really a Courgette
Squash Crookneck is named and described separately from the other eight — its own listing compares its flavour directly against "all other courgettes," which is the supplier's own way of saying it isn't one. It's a related summer squash with a swan-necked yellow fruit, best eaten young when sautéed; left to mature, the skin turns golden-orange, hardens, and develops a warty texture. The plant itself is compact and a very heavy producer, and picked hard it will keep cropping right through the season.
Planting for This Zone
Courgette is frost-tender, and every variety here follows the same temperate window: sow November to February, after the last frost has passed, with harvest running January to April. Space plants a full metre apart, and grow at least two plants rather than one — courgette relies on separate male and female flowers for pollination, and a lone plant is more likely to flower without setting fruit; if that's already happening, see Why Is My Courgette Not Fruiting in NZ Temperate? or Why Are My Courgette Flowers Falling Off in NZ Temperate? for the fuller diagnosis.
The Koanga cultivars add a specific transplant cue worth applying however you raise your seedlings: prick out at 6cm spacing once the first leaves show, then move to final 1m spacing only once soil temperature has reached 15–16°C — a genuinely warm-soil crop, not one to rush out early just because the calendar window has opened.
Ready to plan the rest of your summer bed? Check the NZ Temperate Planting Calendar →.