It has been a real problem for me. My heavy clay is waterlogged in winter - high water table - but baked dry in summer. My plants have to tolerate standing in water followed by drought. It's quite a challenge.
I think a lot of us are going to have to change our gardening style in view of climate change and the past two summers have certainly shown which plants are capable of dealing with drought and heat.
I love the botanic gardens in Cambridge and their dry gardens. I usually visit during the folk festival, cancelled last year and this year too Maybe 2022, I have kept the tickets!!
The past three years in Cambridgeshire we've had extensive droughts and heatwaves. Some (well-known) ideas we are pursuing:
Use suitable (seeking deep roots) trees, shrubs and/or pergolas and trellises to introduce more (dappled) shade - we are lucky with some of that additionally provided by the neighbour's garden.
Adapt plant choice, use more mediterranean (and similar climes) species
Mulch and enrich with organic matter to reduce evaporation.
Have few gaps, e.g. use drought-resistant species such as geranium macrorrhizum, sedums, et cetera.
A 'lawn' with lots of clover, self-heal and yarrow and other interlopers - it never gets watered.
In a drought we manage to go without watering for much longer than we used to, but it's still a work in progress. I fear what the future is going bring.
@Posy we have a somewhat similar problem. Our clay is a bit gravelly and humus-enriched and drains relatively well so we get by. I wonder if there are certain plants that might help penetrate the clay with tap roots or deep roots. But with a high water table that would not matter actually - that combination of yours is really challenging!
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I love the botanic gardens in Cambridge and their dry gardens. I usually visit during the folk festival, cancelled last year and this year too
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