Bog gardening – again

On the grounds that if you are going to get wet, you might as well get muddy, I’ve been working in the teeming rain on the bog garden by the pond. Given the amount of rain the British Isles have had this summer, I imagine a few people may be contemplating starting a bog garden. So I thought I’d go back to a few first principles – learned through hard experience. If you also want a professional gardener’s guidance (plus an excellent plant list) I thoroughly recommend Beth Chatto’s ‘The Damp Garden’ – a book that helped me hugely when I was starting to learn about bogs.

Drainage.

It’s no good just finding a wet patch and sticking plants into it. It’s important to know where the water is coming from, where it is going to, and whether there is any flow through the soil. Plants will die if their roots hit the anaerobic environment of stagnant water.

Other than the purely aquatic ones, only a few plants will tolerate waterlogging for any length of time. The primulas here regularly get flooded, but there’s a drain to one side, so the surface water soon disappears. Ideally, you want the water table to be around about a foot (50/60 cms)  beneath the soil surface.

The quickest way to explore what the water is doing beneath your boggy patch is to dig a hole, watch how quickly it fills, whether the level varies much, and whether the soil at the bottom remains damp during a dry spell. Fill the hole to the brim with a bucket of water and see how fast it sinks back to the previous level. If it lingers longer than  few hours, you probably need to improve the drainage. Here’s a place (it’s supposed to be a path)  where a new drain is definitely needed:

If it’s not clear where your water is flowing to, one solution is to create a soakaway at the lowest point of your bog. Dig as deep a hole as you can manage, drop in a layer of rubble, and then fill it with gravel. Then direct your drainage into it. I always leave my drains open. In my experience, no terra cotta or plastic pipe can cope with very fine clay silt or with primula roots, and digging up buried drains is a far worse task than clearing open ones. I dealt with constructing an open drain here, and in subsequent posts, and I’m at work leading further seepage directly into it.

Access

You need to be able to get to the interior of your bog garden without sinking into the ooze, especially if you take a wheelbarrow. Compacting damp soil by treading on it constantly does no one any favours. So a path of some hard material is probably needed, preferably stones or bricks – on end – .Gravel just sinks into the mud, and if you use slabs and drop one in the wrong place on sticky clay, it’s the devil’s own job to shift it. From an aesthetic standpoint, your path should appear to have (or have had) a function other than just leading you into a bog. I try to disguise mine as a rock shelf.

Plants

Weeding a bog garden is the pits, and to be avoided at all costs. This means choosing plants which are big enough to dominate buttercups and other damp-loving weeds. It also means avoiding small damp-loving plants. This is a sacrifice, but believe me, in the long term, you won’t regret it.  Your plants may look nice and manageable in Spring, but by August you will be deep in the wet foliage trying to save your prize specimens from the rampant jungle. Big is best. And, iIf you have enough space for it, gunnera tinctoria takes on everything around it and wins.

Otherwise, I rely on the ligularia and inula families, plus the big rogersias, and tough, rampant hostas. Iris too, of course. Even the semi-wild montbretia, crocosmia x crocosmiflora is happy in a wet soil and forms huge clumps that suppress any intruders. More refined crocosmia cultivars aren’t robust enough .
But of course, the star of my bog garden, seeding itself everywhere, and totally weed-proof  is primula florindae, just now coming into the full glory of its flowering, its heady perfume at its best in the rain.

Foxgloves and Irises

In this worst of all possible gardening years some plants appear to have taken advantage. Foxgloves have seeded themselves everywhere, and are now in flower. I’ve never seen so many. If they weren’t such a common wild flower, I would be nurturing them carefully because they make for wonderful patches of colour just when the June flowers are going past their best. As it is, I ruthlessly pull the seedlings out of the borders without a second thought and throw them on the compost heap.

The guide marks for the bumble bees give the flower its interest. In a bee’s vision the blotches may line up perfectly, but even with human eyes you can see the landing pad and the surrounding dots which help the bee focus on the right spot. Each flower has a slightly different pattern – is this random, or is it a sophisticated way to attract short-sighted bees as well as the normal ones?

The water irises are coming into flower now too. This is iris pseudacorus ‘alba’, a rather

sophisticated version of the common yellow flag iris, iris pseudacorus. It’s marginally less robust as well, which is fine by me, as the wild yellow version forms large clumps very rapidly – whereas this is more discreet.
My favourite is iris laevigata, especially at this tightly-furled stage. It’s a Japanese iris, and is happiest growing with its roots in water. It has the best blue of all the big bog irises, but I find the full flower fractionally out of proportion to the rest of the plant. A mere quibble I know.

And finally, iris chrysographes, the one iris no one should be without, because the deep velvety purple-black is not only striking in its own right, but usefully sets off almost every other colour you can grow it against. The RHS says it needs well-drained soil, but if my experience is anything to go by, this is nonsense. I grow it in everything from fertile loam to sodden yellow clay. Providing you have a tinge of acid in the soil, it will do just fine.

Candelabra Primulas

Among the vast primula tribe, the candelabras (section proliferae) are the easiest to grow, and hence much loved by gardeners who have a bit of damp and not too much heat. They aren’t especially fussy about soil type – some grow on limestone in the wild – and are, in general, usefully perennial and resistant to abuse. Their chief enemies are slugs (which gnaw out the resting buds) and moles, which can leave the tap roots dangling in the air of their tunnels. They really don’t like heat, though, and can be weakened by too much of it, after which they may succumb to all sorts of horrors.

There are many different ways of using these plants, but I use them to form blocks of colour rather than mixing them up. Their colours are intense, and can clash badly with each other if you are not careful. Some gardeners like  this effect, but I don’t, so I avoid mixed candelabra seed.

Primula ‘Inverewe’ grows happily with me in soggy yellow clay but many people find it difficult. It’s a hybrid, so has to be propogated by division. The intense orange of a bed in full flower is wonderful, but you do need to be a bit careful where you put it, as it dominates everything around it. I find it almost immune to cold, wet, or disease, and it grows happily with its tap roots down to the (non-stagnant) water table.

Primula puverulenta is equally intense in colour – and needs to be kept well away from ‘Inverewe’. It’s a lot more temperamental – largely because slugs will attack any weakened plant – and a lot less fond of clay. It also picks up a virus which stunts the leaves. I grow mine in deep wet compost, but with the roots kept above the water table. It’s a greedy plant and needs annual top-ups of humous-rich material. Part of the attraction is the meal (farina) which coats the stems in silvery yellow. Most of the prolifera are promiscuous in their habits, so you are better to propogate by division if you want to maintain a particular shade (see splittting candleabra primulas). However, p.pulverulenta sets seed readily, and it germinates equally readily, so you can build up a big collection quite rapidly.

For the orange/yellow shade, I rely on p.bulleyana. This is a really tough primula, which will even survive in turf (wet turf). It’s slower than the others to emerge in Spring, and usually flowers a week or two later – which is annoying. It gets mixed in with p.chungensis, which has flatter-faced flowers and lacks the crimson shade in the young bud, but is otherwise very similar. But the general tendency among the proliferae not to be too fussy about interbreeding means that trying to grow distinct species is usually a fool’s game. p.bulleyana refuses to set seed with me, so I divide it now and again. It forms fewer offshoots than the others, so it takes a little longer to build up a substantial block.

Finally (for the moment) we have p.aurantiaca. The virtue of this plant is in the black/dark red flower stem, which contrasts well with the vivid orange of the flowers. It’s smaller than the others, seems to appreciate rather more shade, and likes the soil a bit dryer (though certainly not dry) It’s slow to make clumps you can divide, and doesn’t set seed with me, so you need to take a little more trouble with it. Along with p.pulverulenta it dislikes having its roots undermined by moles, though slugs seem to leave it alone.

These primulas ought to grow in any garden that is reliably damp and reliably cool for the growing season. Winter (as always with primulas) is the time of most danger, unless you can provide good snow cover from October on. p.pulverulenta is particularly susceptible to rotting in mild rain-sodden winters.

One day a year

Once a year, on the second Saturday of June, my garden is open as part of our local summer festival. I used to open it under the ‘Yellow Book’ scheme as well, but this isn’t really a garden visiting part of the world, and the extra numbers weren’t really worth the effort. Besides, I like people to enjoy the garden without having to pay.

The forecast for Saturday is bad, as usual, but it isn’t raining today, so I thought I would run a virtual tour…
We start at the herbaceous border: It’s a late year, so it’s not at its best yet, with the big oriental poppies only just starting, and the black iris chrysographes yet to make an impact. But the plants have grown enough to hide my beech framework – so that’s one good thing. At  the end of the path, the euphorbia ‘Wallenberg’s glorie’ is not quite as yellow as it will be, while the iris siberica ‘Perry’s Blue’ , which should be a spectacular endstop, appears to have only one flower this year. The slugs must have got the rest… 
Turning right, we reach the steps down to the lawn. I see the gardener has left the tractor out again. I apologise. I shall dock his wages.
Half way down, we shall pause to admire geranium ‘Mayflower’ – blooming in June. …
Looking back up from the bottom, you can see my peat walls to the right, with gentians and primulas, and a lurid orange broom, which is supposed to hide the tangle of the lonicera syringantha behind it.
As we walk down the lawn towards the ruin, there is a patch of lupins flowering on the bank. They grow more or less wild in Scotland, but don’t spread here, because they are too busy battling the mice.

Here’s the ruined sawmill and my scree bed, looking quite colourful, though I say so myself. (If at a slightly odd angle)
Just beyond, to the left, there’s a patch of mossy grass where you can stand and inhale the scent of the yellow azaleas – inimitable and intoxicating.

Round the corner we find the Pictish stone, and what should be a flourishing bed of blue poppies set against the floating white blossoms of the rubus tridel behind. The poppies have not had a good year, and the rubus was so frosted that it refused to start leafing up until May -so no flowers. Not a pretty sight. Better turn to your right.

Here at least there’s a bit of colour, although the primula pulvurentula need to get their flowers bulked up a bit. I don’t think the buds enjoyed being covered in mud when they were submerged in the flood.

Beyond the Pictish stone, lies the pond, with primula florindae growing everywhere. There won’t be much colour here before July, so we can move on….

…although you could spare a glance for primula secundiflora on the way.

Up the steps from the pond, we come to what I am informed is my ‘creek’. It’s much changed from its bare Februrary appearance, with all the primulas that grow in its margins just coming into flower. If you will excuse me, we’ll just pop back in time a little so you can see what I mean…
Sorry about that. To continue, before going up the hill, glance to the right….

…where the blue poppies are doing rather better than they are down by the pond.

The upper part of the creek is dominated by primula ‘Inverewe’ and by the big irises, which aren’t in flower yet. So we will retrace our steps and go down the path to the burn…

It’s too shady for much to grow here by way of flowers, but it’s always nice to walk beside running water.

And you can shelter from the sun and have a picnic under this beech (or more likely shelter from the rain and wish you hadn’t brought a picnic)

And so we emerge from behind the ruin, past a rather stunted rhododendron decorum, and return towards the house. That brings us to the end of the tour. Exhausting things, virtual tours, especially hanging around waiting for the pictures to upload. Still, there are cakes and teas for sale at the community hall… See you next year.

Flash floods and other watery diversions

It was typical that when the warm weather arrived in Scotland so too did a thunderstorm which dumped two inches of rain on the garden. The ‘creek’ became a torrent and the pond rose five feet in a couple of hours. My drainage system can’t cope with this sort of thing. I was away at the time, and returned to find the primulas clinging on for dear life, with all their nice top dressing swept away. Bog plants don’t mind being submerged now and again, but when the waters retreated, a fine layer of silt had covered every leaf and flower. What was green is now brown. It’s ironic that I now look forward to some rain to clean things up again.

The sun and the heat mean that it is time to tackle the worst job of the year – cleaning out the pond. I’m looking forward to this even less than usual, because I suspect my waders have perished and are no longer waterproof. The water in the pond is not deep, but there are about three feet of gooey silt under it, so waders are essential.The other essential is a pair of surgical gloves, because there is nothing nastier than putting a bare hand on a newt or any other of the wiggly things that live in the pond (though it’s probably even nastier for the newt). Here’s the scale of the task:The pond seems to have a fairly healthy ecology, and grows a variety of different water weed, but if I don’t clean out the vegetation once a year, it becomes choked. Besides, I like reflections, and pondweed does not reflect. The newts, tadpoles, snails and water-beetles don’t seem to mind, and the weed grows back quite rapidly. There’s also the bullrush (reed mace) problem…This is an amazing plant. Those cables linking parent plant to offspring are just one year’s growth. You can see it is designed to colonise shallow water as rapidly as it can. So it needs to be hauled out, in quantity. Luckily, its sponge-like roots rot down quickly in the compost heap, as does most of the weed. I am sure a pond-weed salad might be tasty – but not today, thanks:I try to save any newts that have become caught up in the weed, and keep a jar of water handy so they can rinse themselves off before returning to the pond:After several hours ploughing through the silt, the job is done. It will be a day or two before the mud settles and I have a mirror-like surface, but already it looks like a pond again, and not a bit of green lawn.(and yes, the waders were perished. Socks and jeans are in the wash).

A plague of Iris

I’ve been cleaning out the upper part of what Linniew is pleased to call my ‘creek’. The winter silt chokes all the pools and needs to be dug out. This involves a great deal of mud, but to spare my readers’ sensibilities, I have not photographed it on this occasion.There’s no fancy stonework here.  I created the pools and falls from some ancient railway sleepers dug at an angle into the ground. The soil is very heavy clay, which never dries. It seems to suit my primula ‘Inverewe’, and the big water-loving irises, so that is what I mostly grow here.The problem with these big irises is that they go on the rampage if you give them a sniff of water and mud. The central clump here is Iris Laevigata which has pretty, floppy dark blue flowers in late June. It used to be a single plant, but has built itself an island. If I failed to hack it out, there would be no pool left. The same goes for the common yellow flag (Iris Pseudacorus) and, above all, Iris Versicolor, a tough American iris with beautiful purple/blue shading on its young leaves. All of them have to be  savagely attacked with a spade, and chucked in the trailer in gooey clumps. Any wild, damp, underpopulated bit of the garden gets a dollop of mud and an iris or two stamped in. Then I leave them to their own devices.

Elsewhere, it’s time to stake the herbaceous plants. Stake is probably the wrong word, as what I do is weave a rough dome of beech branches over the delphiniums, aconitum and the oriental poppies (papaver orientale). The Edinburgh Botanics use birch, and weave it properly: my version is  rough and ready by comparison.There’s a turbulent back-draft off the wall, and if heavy wind and rain combine, flower stems get bashed. The beech provides excellent support, especially to the top-heavy poppies. I support even the smaller plants, such as the Johnson’s Blue geranium, which can look very ugly if it is blown flat. The only difficulty is having to guess the height the plants will grow to, so that the supporting framework is concealed.

After all this work with green leaves and black mud, it’s nice to have something in flower. The spring clematis, c.macropetala, forms a blue tangle at this time of yearDon’t tell Alistair, but I actually prefer these early species clematis – this and the various c.alpina cultivars to the large-flowered summer varieties. There’s delicate, and there’s blatant…..