Succession planting means sowing little and often instead of once — so a bed keeps producing over months instead of dumping one glut and sitting empty. Not every crop supports it. Knowing which ones do, and how wide their real sowing window is, matters more than the general idea.
Three Ways to Succession Plant
Repeat sowing the same crop. Sow a short row of the same vegetable every 2–4 weeks instead of the whole bed at once. This is the classic method and it's what most people mean by "succession planting."
Relay cropping. As soon as one crop finishes, a different crop goes into the same space — timed so the next planting's sow window opens right as the first crop clears out.
Staggered varieties. Plant several varieties of the same crop with different days-to-maturity at the same time, so they finish at different points instead of all together. Less common in a home garden, more useful if you're trying to avoid a single week of glut.
Repeat sowing is the one that actually depends on a crop having a wide sow window — which is where the real data matters.
Crops That Genuinely Support Succession Sowing
These are ranked by how wide their actual sow window is in this site's planting data (NZ temperate and cool/mountain windows are effectively identical here):
Radish — sowable August through April, a 9-month window with only the depths of winter (May–July) closed off. The fastest-maturing crop on this list, so it's also the easiest to succession sow every 2 weeks without a backlog.
Beetroot and Silverbeet — both sowable August through May, a 10-month window. Sow every 3–4 weeks and you'll have continuous root or leaf harvest almost year-round, with only June–July shut out.
Pak Choy — same August–May window as beetroot and silverbeet. Fast-maturing enough that a 2–3 week resowing interval keeps up a steady supply without gaps.
Carrot — sowable September through May, a 9-month window. Carrots take longer to mature than radish or pak choy, so a 4-week interval between sowings is more realistic than 2.
Lettuce — sowable September through March, a 7-month window. Sow every 2–3 weeks for a rolling supply through the whole warm season; the closed window (April–August) lines up with when lettuce would bolt or stall in cold soil anyway.
Spinach — sowable September through February, a 6-month window, but check for bolting risk in the hottest weeks of summer before you sow — spinach is quick to bolt once it's warm.
Coriander and Mizuna — narrower windows (coriander July–November, mizuna August–December) but both are fast growers that bolt quickly on their own, so treating them as succession crops within their window — sowing every 2–3 weeks rather than one big batch — gets more usable harvest out of them than a single sowing would.
Crops That Are One-Shot, Not Succession Candidates
Some crops have a wide-looking sow window on paper but don't actually work as repeat-sow candidates, because the crop takes so long to mature that the whole window produces one harvest flush regardless of when within it you sowed:
Garlic — sown once a year (April–May in NZ temperate, a month later at May–June in cool/mountain, reflecting the extra chill delay already documented in this site's garlic articles) for a single harvest the following summer. There's no succession angle here at all.
Onion, Brussels Sprouts, Broad Beans, Pumpkin — each has a real sow window of 2–3 months, but they're long-season crops that mature together regardless of exactly when in that window you sowed. Stretching your onion sowing across July–September doesn't buy you a longer onion harvest — it just means slightly different maturity dates on a crop you were only ever growing one round of.
Jerusalem Artichoke and Yacon — perennial-habit tuber crops planted once (November–December) and left to bulk up over a long season. Not a succession crop by nature.
Don't force succession sowing onto this group — it wastes bed space on plants that were never going to give you a second round.
Zone Differences That Actually Matter Here
NZ cool/mountain's shorter frost-free season doesn't change which crops succession-sow well — the sow windows above are the same in both zones for nearly every crop on this list. What it changes is how many rounds you can actually fit in before the season closes. Warm-season crops that need frost-free conditions to finish — courgette and tomato, for instance — have their harvest window end a month earlier in cool/mountain than in temperate zones. That's one fewer succession round squeezed in at the tail end of the season, not a different set of crops to plant.
Practical Intervals and Bed Management
Fast crops (radish, pak choy, lettuce, mizuna, coriander): resow every 2–3 weeks. Sow the next round when the current one has just germinated, not when it's ready to harvest — otherwise you'll get a gap.
Slower crops (beetroot, carrot, spinach): resow every 3–4 weeks. These take long enough that a 2-week interval creates more overlapping harvests than most households can use.
Between sowings, top-dress with compost rather than leaving the bed's fertility to run down over repeated crops in the same soil — succession sowing asks more of a bed's fertility over a season than a single planting does. It's also worth rotating which family goes into a given row each round rather than resowing the identical crop in the identical spot every single time, for the same soil-health reasons crop rotation exists more broadly.
Keep a running sow date log. The easiest way succession planting fails in practice isn't the growing — it's forgetting when the last sowing went in. A simple written list of sow dates per row beats trying to remember by eye whether it's been three weeks yet.
Getting Seed for Repeat Sowing
Succession sowing uses more seed than a single planting, so buy accordingly — running out of radish or lettuce seed halfway through the season is a common way this method quietly stops. See the guide to NZ seed suppliers if you're restocking, and check your zone's frost dates before deciding how late in the season to squeeze in one more round.
Ready to map out your own succession calendar? Check your zone's planting calendar →