New bed on a bank

jonathan.cole

We've got an area on a bank that I am struggling to work out what to do with.

It is about 5 metres wide by 2.5 metres deep and on maybe a 40 degree slope. It's being built up with soil from elsewhere in the garden which is clay-based.

The bank faces South but gets quite strong wind. At the back at the top we already have a forsythia and a rose (alba Maxima).

We were thinking cottage garden style, but I'm a bit lost. It feels like it is too steep to follow the usual tall plants at the back, short ones at the front. It will also be bare earth shortly and it would be nice to do _something_ with it.

Any ideas?

Fairygirl

Hi Jonathan, I think if it's quite exposed and windy, you'll need a bit of structural planting in there first. Some shrubs, deciduous and evergreen, which will then help support the perennials and/or annuals you put in. There are loads  to choose from. It might be a good idea to run some narrow paths, or individual standing areas, through it to help when you're in there deadheading, tieing in and generally working in the bed.It can be difficult to avoid standing on plants otherwise!

Are you having an edging of some kind to help retain it though, or just relying on the planting? Some of the horizontal cotoneasters would help with that.

Nollie

I have virburnum tinus, cotoneaster horizontalis, abelia grandiflora,  nandina domestica and a horizontal lime green conifer (no idea what it is) on a south-facing sunny slope that gets a fair amount of wind. They all help stabilise the slope and I plant perennials inbetween.  If you can make two or three stepped terraces, nothing fancy, just level a bit and support the soil with large stones dug in, bits of paving stone, knocked in short posts etc., that also helps.

I also have a nandina domestica hedge forming a windbreak and it gets really battered about, seems to just bend with the wind and pop up again!

jonathan.cole

Thanks both.

It's been fairly stable for the past few years with just grass. I've built it up a chunk with soil being dug out of the rest of the garden to help even it out and give a grass free space to start planting in.

There will be a hedge along the side to break much of the wind, once it grows a bit more. I planted it late 2017 and is a mix of hawthorn, elderflower, dogrose, cherry plum and blackberry.

You've both talked about stabilising, do you think it is really at risk of sliding down the slope then? I hadn't even considered that!

Nollie

The roots of the grass would have knitted the soil on the slope together, now you have presumably dug out all the grass and turned over/added more soil, it will be at risk of eroding/slumping down towards the bottom, especially if you have any heavy rainfall. Hence, ideally, the need for a short retaining wall at the front and creating a series of stepped areas to plant in. This also helps when watering as if the area around the plant is flat, helps to stop the water run off down the slope, exposing the plant’s roots and taking topsoil with it.

Once the new plants are established, their roots will do their own knitting! All depends on what you want to plant and how quickly you can get it established and self-supporting, I guess...

jonathan.cole

Yeah, fair point. Perhaps I do need to terrace it then.

I shall have to see if I have any stone left over after the rest of the walling is done or else get some more sleepers.

Fairygirl

It really depends on what you plant and what your climate and conditions are like too. I'm not sure you need terracing as such, just some level areas which allow access, and it definitely depends on the planting. If you're shifting soil from other areas and it's clay, you'll meed to improve it a bit before planting too. Clay is a wonderful medium, but it can be wet and heavy in winter, and dry and cracked in summer. It would be worth adding plenty of manure to improve the texture, plus compost, and then mix plenty of compost into it each time you plant. 

We had a bank that sort of dimension at a previous house, but the shrubs held everything together.  South-ish facing, but also in the line of fire for all the weather. We didnt have much in the way of airy, fairy perennials though, mostly tougher stuff as the rabbits ate everything else. If the rabbits hadn't been so prevalent, I could have put some perennials and bulbs etc  in between the shrubs.