Mapping what uk counties are in what usda zones is challenging due to the differing climate patterns and microclimates within each county. However, we can make some general observations based on the climate characteristics of different regions in the UK.

1. Southern England:
   Counties: Kent, Surrey, Sussex, Hampshire, Dorset, Wiltshire, Berkshire, Buckinghamshire, Oxfordshire, and others.
   USDA Zone: Generally corresponds to Zones 8a to 9a.
   Description: Southern England tends to have milder winters and warmer summers compared to northern regions. Coastal areas, in particular, benefit from the moderating influence of the Gulf Stream, leading to relatively mild conditions year-round.
2. Southwest England:
   Counties: Cornwall, Devon, Somerset, Gloucestershire.
   USDA Zone: Mostly Zones 8a to 9a.
   Description: Southwest England shares similar climate characteristics with southern counties, with mild winters and relatively warm summers. Coastal areas may experience slightly milder conditions compared to inland regions.
3. East Anglia:
   Counties: Norfolk, Suffolk, Cambridgeshire, Essex.
   USDA Zone: Primarily Zones 7b to 8b.
   Description: East Anglia experiences slightly cooler temperatures compared to southern regions, especially in winter. However, it still enjoys relatively mild conditions overall, with fertile soils and ample sunshine, making it conducive to gardening.
4. Southeast England:
   Counties: Greater London, Hertfordshire, Bedfordshire, Kent.
   USDA Zone: Zones 8a to 9a.
   Description: Southeast England benefits from the urban heat island effect in metropolitan areas like London, leading to slightly higher temperatures compared to surrounding regions. This, coupled with its southern location, results in a relatively mild climate.
5. Midlands:
   Counties: West Midlands, East Midlands.
   USDA Zone: Zones 7a to 8b.
   Description: The Midlands experience a temperate maritime climate with moderately cold winters and mild summers. Inland areas may have slightly cooler temperatures compared to coastal regions.
6. Northern England:
   Counties: Yorkshire, Lancashire, Cumbria, Northumberland, Durham.
   USDA Zone: Zones 6b to 8a.
   Description: Northern England experiences cooler temperatures compared to southern regions, with more pronounced seasonal variations. Coastal areas may benefit from the moderating influence of the sea, while inland regions tend to be colder, especially in winter.
7. Scotland:
   Counties: All Scottish counties.
   USDA Zone: Zones 5a to 7b.
   Description: Scotland has a diverse climate, with milder conditions in the west due to the Gulf Stream and cooler temperatures in the east. Higher elevations in the Highlands experience colder temperatures and shorter growing seasons compared to lowland areas.
8. Wales:
   Counties: All Welsh counties.
   USDA Zone: Primarily Zones 7a to 8b.
   Description: Wales experiences a maritime climate with mild winters and cool summers. Coastal areas tend to be milder compared to inland regions, with ample rainfall contributing to lush vegetation.

These are general observations, and microclimates within each county can vary significantly. Additionally, factors such as altitude, proximity to the sea, and local topography can influence growing conditions. Gardeners should always consider multiple factors when selecting plants for their specific location.