Best Cauliflower Varieties for Scotland

Cauliflower has a reputation for being the fussiest brassicaThe cabbage family: cabbage, kale, broccoli, cauliflower, Brussels sprouts, kohlrabi, swede, turnip and more, sharing the same pests, diseases and rotation rules. Full definition → in the plot, and the ten varieties that carry the RHS Award of Garden Merit don't all deserve that reputation equally. Some are bred to race through a mild summer; others are built to sit through a hard winter and still deliver a solid white head in spring. The difference between them isn't just timing, it's a formally rated difference in cold-hardiness, and that rating is the single most useful thing a Scottish grower can check before choosing seed.

The full growing guide covers buttoning, the three sowing-type windows, and day-to-day care in depth. What follows is the ten AGM varieties compared head to head, plus a handful of genuinely useful varieties outside that list, so you can pick the one that actually suits your ground and your winter.

The ten AGM varieties, compared

The Award of Garden Merit for cauliflower currently covers ten varieties spanning all three sowing types, plus two colour types. The award itself is a UK-wide garden-merit assessment, not a Scottish recommendation, but each variety's own RHS plant page also carries a formal hardiness rating, RHS's scale for how much cold the plant itself tolerates. H3 means hardy in coastal and relatively mild parts of the UK, roughly -5°C to 1°C, milder than many Scottish gardens see in a typical winter. H4 means hardy through most of the UK, -10°C to -5°C, closer to what most lowland Scottish gardens experience in an average winter. H5 means hardy in most UK locations even during a severe winter, the band worth having if your ground sees the sharpest frosts. That rating varies more between these ten varieties than almost any other trait on the list, and it splits cleanly by sowing type: summer and autumn varieties sit at H3, the one winter variety steps up to H4, and the two spring varieties reach H5.

Triomphant appears on the general AGM list, but its own individual plant page doesn't display the AGM mark. The general growing page also credits Jerome with "coping well with cold weather," a phrase Jerome's own individual page doesn't use, that page states the harder, more checkable version of the same claim instead: the H5 rating itself.

Two more entries didn't make the RHS's own AGM list but are worth knowing about anyway. Aalsmeer, a spring type, carries the same H5 hardiness rating as Jerome and is described on its own page as having "outstanding Winter hardiness," with harvest also running March-April, a genuine second option in the one slot where cold-hardiness matters most, though it hasn't been awarded the AGM. Gardener's World separately names Walcheren Winter Pilgrim, "winter hardy with creamy white compact heads," and Depurple, a purple variety, as varieties worth growing outside the RHS AGM list.

Picking by trait, not just by hardiness

Hardiness only decides the choice outright at the coldest end of the calendar. If your plot has lost brassicas to a hard winter before, or sits somewhere colder than the mild, coastal fringe the H3 band describes, Jerome (or the non-AGM Aalsmeer) is the one choice on this list with a rating built for that. For every other slot in the calendar, summer, autumn, autumn/winter, hardiness doesn't separate the field, so the deciding factor is a different named trait: club root resistance for Clapton, "stands well until harvest" foliage protection for Moby Dick, pinking resistance for Raleigh, or simply which harvest window you need filled.

Pinking: a second cold-stress defect, distinct from buttoning

The growing guide covers buttoning, a check in growth that produces a small, premature head, in detail, since it's the crop's best-known failure. Raleigh's own page names a second, different curd defect: "pinking," a discolouration of the curd surface, and states plainly that Raleigh "copes well in stressful conditions and is resistant to" it. Where buttoning ruins the head's size, pinking is a cosmetic defect that shows up as the head is otherwise developing normally, but both are provoked by the same underlying conditions: cold and stress during curd formation, exactly what a Scottish spring or an unsettled summer supplies. Raleigh's stated resistance to it is a genuine, named trait none of the other summer varieties here claim.

Coloured and romanesco types: same crop, same rules

Graffiti and Veronica both carry the AGM and both grow exactly like white cauliflower, same sowing windows, same spacing, same care, the colour is bred in, not a sign of a different or more delicate plant. Graffiti's own page is specific about one point worth knowing before choosing it: the purple curd "become[s] darker the more they are exposed to sunlight," so a shadier plot will produce a paler head, worth weighing against a north-facing or overcast Scottish site before choosing it for colour alone. Veronica's romanesco florets are described on its own page as "densely arranged in whorls," and its page lists spacing slightly tighter than the standard range at 40-50cm between plants and 50-60cm between rows, worth checking against seed-packet instructions rather than assuming the crop's general spacing figures apply unchanged.

Both pages flag the same disease vulnerability as most of the white varieties here: Graffiti's own page lists susceptibility to black rot, club root, downy mildew, foot and root rot, leaf spot and white blister, and Veronica's notes it "may be susceptible to club root." Neither colour type is described anywhere as more resistant than the white AGM varieties, the colour is a cosmetic and flavour difference, not a hardiness or disease advantage.

Soil, and the one thing every variety on this list shares

None of the ten AGM varieties are described anywhere as more or less demanding on soil pH, that's a crop-wide figure, not a variety one. Cauliflower prefers a soil pH around 6.5, and liming very acidic ground both raises the pH and helps deter club root directly, the single most consequential brassica disease on Scotland's naturally acidic soils; the growing guide covers the timing and rotationMoving each crop family to different ground each year, on a multi-year cycle, so pests and diseases that build up in soil don't get a repeat host. Full definition → detail behind that. Clapton's named club-root resistance is worth more on ground that's already acidic and hard to lime fully than on ground where the pH is already close to 6.5, the variety and the soil treatment work on the same problem from two directions, not as alternatives to each other.

Scotland isn't one climate, either, and the split isn't simply north versus south: it's elevation. An upland garden sees harder, later frosts than a lowland one nearby, whatever region it's in, which is exactly where Jerome's H5 rating earns its keep more directly than it would in a milder lowland garden.

Which one for your situation

Building a near-year-round spread from this table means sowing several types in succession rather than picking one: Tirza first, a summer or autumn type for the main crop, and Jerome to finish through the coldest months, each with its own sowing date and its own space, not one planting stretched across the calendar.

Seed availability varies by supplier and by year, check current stock before committing to a specific variety, especially the less common ones like Aalsmeer or Walcheren Winter Pilgrim, which aren't on the RHS AGM list and are correspondingly less widely stocked.

Watch for these pests and diseases whatever you grow

Every variety checked here shares the same brassica pest and disease exposure: club root, cabbage caterpillars, flea beetle, cabbage root fly, slugs, pigeons, and, named specifically on several of these varieties' own pages, downy mildew. None of the AGM varieties above claim resistance to more than one of these; Clapton's club-root resistance is the single named exception across the whole list.

The harvest windows above are UK-wide figures. Scotland's shorter, lower-light winter and spring days can push a hardy spring type like Jerome or Aalsmeer later than the stated window, since curd formation slows with the light rather than stopping outright, worth treating "late March-April" as an earliest-case estimate for a Scottish garden rather than a guarantee.

Common questions

Sources