Rocket shares a plant family with kale, cabbage and the site's other brassicas, but it's the only crop of its species here and genuinely doesn't cross with any of them. It still needs isolation from other rocket varieties specifically, since unlike lettuce, rocket's flowers need insects to carry pollen between plants. Its real story is speed -- ready in as little as 4 weeks -- and a variety swap: standard rocket bolts fast in heat, so wild rocket takes over for summer sowings.
Water need
Consistent moisture keeps growth steady and the flavour milder -- drying out speeds bolting and makes the leaves noticeably hotter.
Calories at a glance
370 kcal/kg -- the highest-calorie leafy green on this site, though still far below any calorie staple (scale is log-based across all 55 crops in the calculator).
Temperature Range by Month
Month on the bottom, temperature up the side. The pale green background is what the plant can survive at all -- fatal above or below it, labelled directly on the chart where that applies to your zone. The coral band is its ideal range, and only fades in during the months this zone would actually have the crop in the ground -- reusing the exact same sowing/harvesting data as the calendar further down the page. The blue line is real monthly climate data (not a modelled estimate) for a representative rural/agricultural location in this zone -- a small farming town or agricultural research station rather than a major city, to avoid the warmer bias city weather stations have. For the actual verdict on how well this crop does in your zone, see the badge at the top of the page -- that's based on the site's own researched yield figures, not this chart.
Quick Start: Sowing to Harvest
- Sow direct, little and often. Sow direct, thinly, every 2-3 weeks through your zone's sowing window to keep a continuous supply coming rather than one glut.
- Switch to wild rocket for summer sowings. Standard rocket bolts quickly once it gets hot -- sow wild rocket instead for sowings made in the warmest part of the season, since it holds its leaf quality for longer.
- Keep watering even. Consistent moisture keeps growth steady and the flavour milder -- drying out speeds up bolting and makes the leaves noticeably hotter and more peppery.
- Harvest young and often. Pick leaves while young for the mildest flavour -- rocket gets progressively hotter and more peppery as it matures, especially once it's under any stress.
- Eat fresh. Rocket doesn't store the way root crops do -- pick only what you need and eat it within a day or two for the best texture and flavour.
Sowing & Harvesting Calendar
Pick your zone under "Temperature Range by Month" above and this updates too. Rocket's window is wide enough for many successive batches within it, the same shape as radish or lettuce's calendar.
Calories & Yield
Rocket is modest but the highest-calorie leafy green on this site at about 370 kcal per kg. Subtropical, Mediterranean, Maritime and Continental zones all give the same best yield here.
| Climate Zone | Yield per plant | Calories per plant | Viability |
|---|---|---|---|
| Tropical / Humid | 0.10 kg | 37 kcal | Viable |
| Subtropical | 0.12 kg | 44.4 kcal | Viable -- best yield |
| Mediterranean | 0.12 kg | 44.4 kcal | Viable -- best yield |
| Temperate Maritime | 0.12 kg | 44.4 kcal | Viable -- best yield |
| Temperate Continental | 0.12 kg | 44.4 kcal | Viable -- best yield |
| Cool / Boreal | 0.08 kg | 29.6 kcal | Viable |
| Arid / Semi-Arid | 0.06 kg | 13.32 kcal | Viable -- challenging (60% yield) |
| Highland / Alpine | 0.08 kg | 29.6 kcal | Viable |
Figures per plant sown, from the site's own crop database. Arid's yield already reflects the 60% penalty the calculator applies where a zone is rated "challenging" rather than fully viable. Rocket is viable in every one of this site's eight zones.
Varieties Worth Knowing
Rocket varieties mostly vary in how peppery they get -- from the mild standard type to genuinely hot ones. All the varieties below are open-pollinated (OP), meaning seed saved from them breeds true and is worth keeping under this site's seed-saving approach; none are F1 hybrids.
Seed Saving -- Quick Guide
Rocket is largely self-fertile with low crossing risk. Note that "wild rocket" sold in salad mixes is a different species entirely and won't cross with salad rocket.
SERVINGS, NOT DAILY CALORIES This works out plate-sized servings of rocket from your seed during its fresh harvest window only, not your group's full daily calorie needs. For that, use the main calculator.
Estimated for your selected zone above, using this site's own germination, loss and yield figures for rocket -- a helping is roughly what you'd put on a plate as part of a meal with other veg. Treat it as a planning estimate, not a promise.
Storage & Preservation
Rocket isn't described as a storage crop in the site's own crop data at all -- it's grown to be picked young and eaten fresh, typically within a day or two.
There's no meaningful way to preserve rocket for the long term -- its role here is fast, fresh variety through the growing season, kept coming by succession sowing rather than by storage.
Growing Rocket Without Bought Inputs
Flea beetle is the main pest to watch for, riddling young leaves with small holes -- the same brassica-family pest that troubles kale and turnip elsewhere on this site, despite rocket not crossing with either.
Fine mesh from sowing onward is the simplest input-free defence against flea beetle, and matters more here than on slower crops since rocket has so little growing time to spare before harvest.
Consistent watering reduces stress-driven bolting and keeps the leaves milder, which indirectly helps too -- a stressed, bolting plant is generally less resilient to pest pressure than a well-watered one.
Frequently Asked Questions
Does rocket cross-pollinate with kale, cabbage or the other brassicas on this site?
No -- despite being in the same family (Brassicaceae), rocket (Eruca sativa) is a different genus from kale, cabbage, broccoli, cauliflower, Brussels sprouts and kohlrabi (all Brassica), and from turnip, swede and radish (Brassica and Raphanus). It's the only crop of its species on this site, so it doesn't cross with anything else grown here.
If rocket doesn't cross with other brassicas, does it still need isolation?
Yes, from other rocket varieties specifically. Rocket is self-sterile -- its flowers need insects to carry pollen between different plants, and won't fertilise from their own pollen alone -- so genuine isolation distance matters if you're growing more than one rocket variety for seed.
How cold and hot can rocket survive?
Roughly -3°C to 29°C, tolerating light frost reasonably well. Heat is the real limit -- standard rocket bolts fast above about 21°C, which is exactly why the crop database recommends switching to wild rocket for summer sowings.
Why does the crop database recommend wild rocket for summer?
Because standard salad rocket goes to seed very quickly once temperatures climb, while wild rocket (a different, more heat-tolerant type) holds its leaf quality for longer through hot weather -- a practical variety swap rather than a change in growing method.
Is rocket a good calorie crop for self-sufficiency?
Modest -- around 370 kcal per kg, actually the highest-calorie leafy green on this site, though still far below any calorie staple. Its real value is speed and fresh variety, ready in as little as 4 weeks.