Suggestions please for plants for heavy clay soil
Roses do well in clay, but nevertheless, I would improve it first with lots of organic matter such as compost or well rotted farm yard manure. Improved, a clay based soil can be very fertile and many plants will grow well. Unimproved, most plants will sulk, sat with their roots in sodden clay in winter, and set like concrete in summer.
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Isle of Wight.
It's a good idea to find out whether your clay is alkaline or acidic and also how wet it is, generally, over time. Many people talk about clay soil but in fact, they can mean different things. You may have a layer of top-soil with clay underneath; it could be clay with some loam mixed in or it could just be solid, airless clay. The solution is to dig in as much muck and grit as you can, as Fidget says, but the answer to the questions about the nature of the soil will still affect your planting.
west central Scotland
Like the others have said - the best approach is to get the soil in good order, and then you'll have more scope. Clay is a great medium for many plants, and if you can addloads of well rotted manure and/or grit, plus compost, that will make it easier to grow plants of all kinds.
Also - can you give some more info about your plot? Aspect for different borders/beds, whether it's sheltered or exposed, general climactic conditions, elevation and so on. That helps enormously with suggestions
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