Otago holds onto frost longer than nearly every other region in New Zealand. Even at the coast in Dunedin, ground frost averages over fifteen days in July, and inland areas run considerably colder again. The region's frost risk typically doesn't clear until November, and in a cold year it can push later still, which makes patience the single most useful trait an Otago gardener can have in spring.
The reliable cool-season crops aren't affected by any of this: lettuce, spinach, silverbeet, peas, beetroot, carrots, dwarf beans and swede all go in safely from September regardless of frost risk. It's the warm-season vegetables where Otago genuinely diverges from the rest of the country. Tomatoes, pumpkin and sweetcorn need real patience here, and several crops that go in easily further north, including broccoli, cauliflower and cabbage started as spring seedlings, are better held for a more forgiving planting window later in the season inland.
Basil and other tender herbs are worth starting undercover well into November here, since Otago's actual last-frost timing runs later than most national planting guides assume. A garden that follows a Waikato or Auckland timeline in Otago is planting into real risk, not just being cautious. Once the season's warmth does arrive though, Otago's long, bright summer days make up ground fast, particularly for anything that had the patience to wait for them.
Basil and other tender herbs are worth starting undercover well into November here, since Otago's actual last-frost timing runs later than most national planting guides assume.