On a Chalk Hillside – April 2024

Published: April 3, 2024

This being a gardening column you would naturally expect me to major on all the ferns I have collected into my new fern bed, and I will be introducing some of the plants in between my explanation of how we created the fern bed planting opportunity on our new bit of chalk hillside in this article and continuing with more planting details next month. To give you a taste, here is the schematic plan of the bed with the planting list himself painted for me in February '21 :-

Some ferns I bought, and some I collected from elsewhere in my garden, or other people's.


This is how a lot of my visits to family and friends end – with a box or bag full of plants dug from their garden – in this case, after our visit to my step mum in Nov '19 I mentioned last month, I came away with many Harts Tongue Ferns (), Male Ferns (Dryopteris felix-mas), and a few roots of Chinese lanterns () for our garden. All of the ferns were dug out of crevices in her drystone wall or steps, and I have learned over the years of doing this that they need to grow on in pots for a while before putting into the garden as they are generally too small to survive as I rarely get all the root out with them when I lever them out.

Our efforts to create such a big change to the contours of this garden were done in stages, during the “building months” which in our case is generally later September – November, and depending on the weather Jan-March each year when we are less involved with sowing/growing/weeding/watering and general horticulture in both the decorative and vegetable gardens. So bits had been done to the hillside such as removing the flags on the old patio; breaking up the concrete block under some of them; and beginning to clear the site of turf in previous years but starting to dig out the hillside began in earnest in September '17.

Here's an early shot:-


What I am doing is working across in a layer, taking it down to roughly the same depth, then starting again back at the beginning and doing it again, and again, until we reached the required depth. This was done with forks and pickaxes to loosen; spades to shovel out (a shovel is too heavy for me to wield) and then barrowed away for disposal. As you can see below, some material is kept for either hardcore; backfill behind the gabion wall; or even a smattering of topsoil I hoped to reuse:-


By the end of November, I had cut into the chalk hillside so much that we had shuttering up to stop the fine chalk from collapsing onto me as I worked:-


You might have been forgiven for thinking we were making headway. However, with the storms in the following fortnight, the shuttering had collapsed by mid-December. Himself had an operation on his hand at the end of November, which put paid to anything else happening on this project til the following September. We then had to make good the subsided materials, and sort out our levels, before starting to put in a hardcore base for the gabions to sit on:-


As you can see from the photo we consumed our own smoke, with the concrete recovered from the patio that had been dismantled. All this I carried to the position for himself to smash up with the lump hammer. A slow job for both of us.

As an aside to all this building work, having been inspired by the Fernery at Kingston Lacy – which is underplanted with snowdrops among the deciduous ferns, I also wanted to include snowdrops, and too. Here's a couple of shots of the fernery on our visit in February 2016 to give you an idea:-


So I have included two types of snowdrops in our fern bed – Galanthus nirvalis as you can see above, and Galanthus woronowi which are a brighter green leafed snowdrop, as well as the Fritillaria meleagris, here in our fern bed with the Woodwardia fimbriata fern behind on 11th April 2022 :-


I had accidentally bought two of these Woodwardia fimbriata ferns (Chinese Chain Fern) from two separate nurseries – they can get to 1.2m x 1.2m if they like you. They like shade and shelter, and I had spaced them against the gabions at the back of the bed with mainly bulbs and logs around them. This one you can see has survived – it has still not reached a metre tall – but the other one a matter of 3 m to the left of it, was never very happy, and after two years did not make any new fronds has withered away.

Back to building! 21st September 2018 we took delivery of the flat-packed wire gabion baskets, and eleven tons of stone to fill them:-


All this had to be loaded onto wheelbarrows rock by rock and barrowed more than 46 meters down the garden to the site. We piled a good amount up in front of where we would need to use them to fill the gabion baskets, and over several days gradually took more and more down until we had filled all the baskets and wired them all shut. Here are shots showing the baskets being placed with their special porous geotextile membrane behind them to stop the soil getting through, but allow water through and wired together for strength:-

closeupwiring basketstogetherwith fleecebehind

Then it is a case of stacking the rocks in the baskets – the front face has to be done carefully so that it is considerably more like building a dry stone wall, but within a metal cage that is deeper than my arms, so is quite a challenge to begin with. The better you can lock the stones in the better it is – here is my first effort on 1st October 2018 :-

beginning to make the goodfrontfaces

And here is a gabion completed:-


As we had thirteen of these baskets to fill, at the back of the basket we filled it with flints/bricks etc which are not seen, and faced it with this decorative stone.

Once we had completed the gabion wall we were aiming to complete the back-filling behind the gabions to be the hardcore for the patio to be relaid above it, but other commitments slowed that down, and then new priorities in the spring of 2019 meant that yet again it was left until August 2019 before the fern bed was constructed and planted.

I had been buying up ferns at any gardens we visited, as well as the ones I showed you above from my step Mum's garden, ones I had rehomed over 10 years previously from my sister's garden, and a few mail order, but at the beginning of August, I started “seriously” collecting ferns for the new bed – via several specialist nurseries that were exhibiting at RHS Wisley in a Fern Show.

I spoke to all of them about the chalky conditions and asked if particular ferns would like that – in the main they steered me correctly, though I took a chance on some Blechnium spicant that really didn't like chalk and certainly didn't survive the first winter. I potted them all up into slightly bigger pots as they needed it, and on 8th August 2019 here's what my “bought” collection looked like, all corralled together:-

ferns growing on in pots

As you can see I had tried to buy them as small plants so they would grow on once planted, rather than as large expensive specimens – after all, enough plants for a 14 metre long x 1 metre wide bed is A LOT of plants. Here's a close-up of all the leaf shapes and colours:-


A shot of two types of fern that haven't done as well with me as I hoped – the Japanese Painted Ferns, and the Maidenhair Ferns (Adiantum pedatum):-


I think I am on my third try with the Japanese painted ferns, buying a different one each time and keeping my fingers crossed. This first one was Athyrium ‘Ursula's Red'. When will I accept that they liked my London clay, and they DON'T like my chalk hillside!

At this point, the largest bought fern was ‘Cristata the King' that had grown on well:-


Next time constructing the fern bed, and planting it up.

Sheila May