Use this guide to choose tropical-looking plants suited to your part of the UK and to understand when winter protection is needed.
JungleBotanics uses the official RHS hardiness scale alongside a plain-English outdoor suitability label. The rating is based on the lowest temperature a plant is likely to withstand, but winter wet, wind exposure, drainage, plant maturity and frost pockets also affect survival.
UK outdoor tropical plant hardiness map
The colours show the plant rating that is usually the safer starting point for each broad region. Gold highlights indicate places where H3 plants may succeed in especially mild, sheltered coastal or urban microclimates. For coastal Thanet, H3 can be possible in a protected garden, while H4 is the more dependable choice for routine outdoor planting.
JungleBotanics UK outdoor labels
| Shop label | RHS rating | Approximate minimum | How to grow it |
|---|---|---|---|
| Indoor or heated greenhouse | H1a | Above 15°C | Do not place outdoors except briefly in reliably warm conditions. |
| Summer outdoors only | H1b–H1c | Above 5–10°C | Move outside only after frost and once nights are warm; bring indoors before autumn cold. |
| Frost-free outdoor site | H2 | 1°C to 5°C | Suitable for frost-free sites or containers that can be moved under protection. |
| Mild and coastal gardens | H3 | -5°C to 1°C | Grow in sheltered, well-drained gardens in milder coastal and southern areas; protect during severe cold. |
| Most UK gardens | H4–H5 | -15°C to -5°C | Generally suitable outdoors across much of the UK when its drainage, moisture and shelter needs are met. |
| Hardy throughout the UK | H6–H7 | Below -15°C | Suitable for colder UK regions, subject to the plant’s other growing requirements. |
How to use the rating
- Check the individual product page rather than relying only on the collection name.
- Treat young plants, newly planted specimens and variegated cultivars as less resilient than mature established plants.
- Improve drainage and shelter plants from cold drying wind; winter wet can be as damaging as low temperature.
- Plants marked “summer outdoors only” should normally go outside after local frost risk has passed and return to protection before nights fall below their stated minimum.
- In coastal Thanet and other mild gardens, a warm wall and sheltered microclimate may improve survival, but it does not change the stated rating.
Important
These ratings are practical guidance, not a survival guarantee. Local conditions can vary within the same postcode. Check the forecast and protect or move plants during temperatures outside their stated range.