recommendations requested & what planting criteria do I have?

verbenawebb

Good morning - does anyone have any recommendations for me for one of my garden beds? the below is loooong... you may want to get a coffee if you commit to reading this 3m south facing bed - sun from 11am to 5.30pm in high summer, in a very hot s/w facing garden in North Devon - the main garden is stepped down and very sheltered. Because it is lower than all surrounding gardens, it seems to collect ALL local ground water so the soil is very wet (boggy in winter) at the bottom level but generally clay. I have a 1ft raised bed due to bogginess banked by sleepers, planted with a huge trachelospermum jasminoides (grows well), pink and red climbing & shrub roses (mainly DA - the young English roses grow quite spindly but Roseraie d'lay is happy as Larry), alpine strawberries on the edges (grow like weeds), and catmint (very happy, too happy, I hate the smell!). I have a philadelphus l'etoile which seems happy but didn't flower a lot last year. Things that have died without obvious neglect are: annuals, lavender, most other soft herbs, clematis Mme Julia something - the common dark red one (never grew back following year), clematis early sensation (tried to cling on last year but I have little hope for it, only grew to 1ft tall in 2 years), salvia amistad (never grew back following year), sunflowers (disappeared overnight - snails?). Bulbs never see the light of day once planted. Weirdly I planted a courgette in there once with minimal attention and it loved it but it looked odd in a flower bed. Weeds that are particularly happy in my garden and now my declared nemeses: rosebay willow herb and sedge. The soil in the bed is now 3 years old and was a collection of compost and top soil - I am sure the existing plants have reached down to the clay goodness below now, but the top 1ft of soil is dry and dusty and useless unless you're a weed. Replacing it is not an option. Does this collective plant profile suggest a particular growing criteria and other plant family recommendations? it's dry but wet and the successful plants don't seem to fit a specific profile. I would like to find a couple of somethings (either bushy/spreading or that I can plant en masse) that takes care of themselves like the nepeta does to tie in the height differences between low-mid height nepeta (2-3ft?) and 5-6ft climbers along the back but in a shade of richer pink / purple to counteract the misty pastel lilac clouds of nepeta particularly before the pink roses kick in in July / august. I would also love to find some evergreen ground cover to mix w strawberries, suppress weeds and fill the bottom 30cm gap under roses, any colour! I used to be a very hands on gardener with big dreams of a cottage garden haven but now I find I have bitten off more than I can chew. In the summer I water once a week deep and weed / prune once every three to four weeks and this seems to keep things just about alive but I don't have a lot of time for intensive attention (yep I know, I have roses :-z - overambitious when planted). Any ideas really appreciated and congratulations if you got to the end of this essay!

BobTheGardener

Have you been regularly feeding those raised beds which are filled with the 3-year-old compost/topsoil mixture?  Did you dig and break-up the clay soil below, before you filled them?  The reason I ask is that if the compost was commercial multi-purpose stuff and the topsoil was bagged, there'll be very little nutrition left if in it by now, and you need lots of soil organisms (especially worms) to keep the soil healthy and self-sustaining.  If you haven't been feeding, I would suggest you mulch the soil now with between 2 and 4 inches of well-rotted farmyard manure (bagged stuff from garden centres is fine), digging more into areas which are currently clear of plants and leaving it on top of the soil around existing plants and shrubs.  The composted manure will give the essential soil ecosystem a huge boost and will result in those areas becoming much more fertile for plants over time, especially if you do the same every year.  The extra organic matter will also help retain water, so less summer watering will be needed.

Clematis need a very rich soil and a deep root run, so the soil in the planting area needs to be cultivated deeply (to at least 50cm) and lots of organic matter mixed-in before planting.

One common issue with clay-based soils is that of 'sumping', where the ground wasn't broken-up sufficiently to create good drainage and then planting holes were dug into the clay and filled with a lighter growing medium.  What happens in that situation is that the water from the surrounding clay drains into the bottom of the planting holes, creating a sump of waterlogged soil at the bottom.  The majority of plants, shrubs and trees will not cope well with that, if at all.

verbenawebb

hi Bob - thank you for your reply - I did dig through as much as I could initially and replenish in year 1 & 2 but not last year, so I guess that is job no: 1 before I make a plant Wishlist :-) yes re sumping - lots of advice taken from GW a few years ago and so to try to combat this, we installed a soakaway underneath a pond, planted a couple more trees and a laid a series of special pipes to the soakaway, one of which runs underneath the flowerbed all along it to hopefully help w that - the water does drain more quickly now. 

so job 1: source some manure! :-)