New raised border - what soil?

WildFlower_UK · March 2023

We are creating a new border in our garden (see the black covered area in my photo), and I'm wondering what to fill it with. We're slightly raising it because our ground is very dense - we have clay soil - making it very unworkable and limiting. Last Autumn I did, however, remove the turf and add a layer of manure before covering it, which I hope will help to loosen it up a little so we don't have to dig/turn it over before adding the frame and filling it. We're raising the border the height of scaffold boards and the new plants will have access to the existing ground below. We did something similar on the other side of our garden where we created a raised veg bed.

The border is in the shade from around midday in the summer, so I plan to plant up mostly woodland and shade-loving plants (ferns, foxgloves etc - still deciding and may be back to ask for suggestions!). My question is, what sort of mix should I fill it with? In my raised veg bed I used this mix, and was thinking of using a similar mix assuming it's still the right mix for permanent planting? We want to buy from this place (it's local and we can get a discount) so if this isn't their best option, what else from their soil/compost options might be? Thanks in advance.

februarysgirl · March 2023

I have raised beds and just use Wickes own topsoil, I've actually been doing my annual top up today. I have perennials, annuals, shrubs and fruit trees in them and everything grows really well. Aside from a little chicken manure for the fruit trees and farmyard manure for the roses, I don't add anything else.

nick615 · March 2023

Who owns the fence? Won't soil rot it? The way the boards are positioned on the neighbour's side suggests it might cause you problems?

Fairygirl · March 2023

You'll need to protect the fence properly first, before you fill the bed, as already said. Regardless of who owns it.
A soil based mix is always best, regardless of what you grow, as the level drops over time. If you're in a drier area, and it isn't in the path of the prevailing rain [I'm guessing it's not, from your description] and want those sorts of plants to thrive, you'll need a fairly substantial mix that doesn't dry out too readily.
It'll still need decent drainage, so plenty of organic matter too, or - if you have the budget, some grit or pea gravel mixed in. Regular additions of organic matter but not any additional food is better for that type of plant

WildFlower_UK · March 2023

Thanks @Fairygirl @nick615 - I should have said that I had already though of that, as the bed we are building will be four-sided built with scaffold boards, and won't be touching the neighbour's fence. There will be a small post-deep gap between our boards and the fence.

@Fairygirl the mix I linked to is 60% soil and 40% manure, is that 'soil-based' enough, as you suggest? Or should I go for this topsoil?

Fairygirl · March 2023

I've never had to buy large quantities of soil, so it's difficult to know.

When I do my raised beds, which I've done many times due to conditions here, I usually re use the turf I lift by putting it in the bottom, then top up with a mix of any old compost or soil, depending on what I'm growing in them. It depends on the height of the bed too.
I used to work in a stable, so I had access to plenty of manure for the beds which were much lower, and were basically just created on old compressed grass. I just removed the turf [used that for the higher beds] and then added the manure, and covered it with plastic and a layer of bark on top to avoid it being too hideous. After about 6 months, the bed was great. The bark got mixed in too. Compost was just added when anything was planted. I'd therefore say your 60/40 mix would be fine.

Leaf mould is a great addition too for that type of planting, but - like home made compost, you need the material for it to start with. Something for you to consider for later on perhaps?

WildFlower_UK · March 2023

@Fairygirl Thanks so much, that's all very helpful

Our garden is quite small so access to enough leaves to create our own leaf mould, or organic matter to make enough compost, isn't possible, so we're having to bring it in. But we got the boards for free and the soil mix should only cost around £90, so in all, it's not bad for a 7m long border I think!

Nollie · March 2023

Just a tip from experience! Make the gap between the bed and the fence big enough to get in a stiff brush in to clear out the accumulation of organic detritus that might get wet and soggy and still potentially compromise the bottom of the fence.

Woodland plants presumably like a deep mulch of decayed woody and green matter, including leaf mould as FG says, as that would be the conditions in their natural environment. Does your council offer composted green waste?

Fairygirl · March 2023

I used to have good trees in the previous gardens for leaf mould, but this one doesn't have any suitable ones. I got a load from a girl round the corner as she's opposite the small NT garden and they get all the beech leaves every year. Wind is in the right direction for them getting into those gardens! The chap across from me was raking up the leaves from his maple so I got a load from him too. Unfortunately, that tree had to come out last year due to root damage to the drains.

The only problem I have is finding enough room for them. I didn't collect any last year because of that. They take a while to break down.

Our council here offers sweet FA @Nollie, otherwise I'd be first in the queue...

It's worth investigating though @WildFlower_UK.
Sounds like you're doing fine with what you're already doing though.

JennyJ · March 2023

Seconding what @Nollie said - make sure your broom, hoe etc can fit into the gap to get rid of the weeds and accumulated detritus that will collect in there. It'll be irritating if you have to get in there and clear it by hand every time.

New raised border - what soil?

Posts