How Do You Create A Bog Garden?

Bog gardens can be a great way to add a valuable wildlife habitat to your garden. They will attract a similar range of creatures as a pond would do, such as frogs, toads, dragonflies, bees, and butterflies. There are an extensive range of bog plants available, which means that it will also be an attractive visual feature.

Bog gardens can be a way to make use of a naturally wet patch of garden, as an alternative to drainage, or they can be adapted from a pond that is disused or leaking. They can also be formed at the edge of a pond, to create a softer boundary with the rest of the garden fed by the pond, or created artificially, and topped up with rainwater collected in a water butt.

They are less costly and take less effort to maintain than a full pond, and if you have young children, you may feel it is a safer option. Bog gardens can be any size, and even created in a container, if your garden has no suitable place for a larger soggy area.

If you decide to make a larger bog garden, you may want to consider adding stepping stones for ease of maintenance. These can make an interesting visual feature in themselves, as well as providing a landing point for wildlife, and a platform to let frogs and insects exit the wet ground.

The plants should be chosen for their ability to thrive in damp conditions and soil with high nutrient levels. Some bog plants prefer more acidic soils, while some prefer alkaline or neutral soil. They may vary in the level of dampness they prefer, so bear this in mind when positioning the plants. Also check out if they like sun or shade, or a mixture of the two.

Once you have the site for your bog garden, mark it out with sand or string. Dig the area out to 30cm to 45 cm in depth, and line the hole with a butyl pond liner, weighing the edges down with bricks to stop it moving about too much. Make several drainage slits in the liner, or pierce it with a garden fork at 1m intervals.

Add a layer of gravel a couple of inches deep to the liner to prevent the drainage holes from becoming blocked, then return the excavated soil to the hole, topped up with organic matter. Avoid compacting the soil tightly. Use collected rainwater to thoroughly water the soil. If this is not possible, leave tap water to stand for a few days before adding it, to allow the chemical levels to reduce.

If you have a naturally wet patch of garden, you may not need to add a liner, and you can simply turn the turf over. However, some plants prefer the greater drainage that is provided by a lined area.

Now you are ready to plant up the garden. Choose a mixture of taller plants to provide shelter for wildlife, and a range of flowering plants that will add colour throughout the year.  Any of the marginal plants on our website will be happy in a bog as long as it is reliably damp, but the bog garden section includes both true bog plants (which cannot be grown in the pond) and suitable marginals, with caveats below.

Because you are planting in one large border as opposed to individual baskets in the pond you do need to be careful to avoid plants with very vigorous root systems which may get out of hand and take over the bog.  So we would avoid some of the more vigorous reeds and rushes like the Reedmaces (Typhas), Sweet galingale, Reed sweet grass and Branched bur reed amongst others.  Also you should be wary of Water mint and the Houttuynias, and Yellow flag iris will take over if left to its own devices.  That’s not to say you can’t use these if you are happy to actively manage your bog garden, and some can be restrained by planting in baskets in the bog.

There is a huge variety of plants to choose from with many attractive ferns both native and non-native which particularly like part shade and provide lovely texture and structure, to many varieties of colourful primulas including the native veris and vulgaris.

Larger areas can accommodate the impressive and almost prehistoric Gunnera mannicata, or if space doesn’t allow the smaller Chinese rhubarb (Rheum palmatum) or the very pretty but still very impressive Darmera peltata.  There are many varieties of Astilbe of all sizes that like damp conditions and Rogergersias provide both lovely foliage and attractive spires of flowers.

Popular native species which are wonderful for wildlife, in particular the pollinators, are Devil’s bit scabious, Meadowsweet, Hemp agrimony, Ragged Robin, Skullcap and Sneezewort.  Finally I think every bog garden should have a few clumps of the stunning Snake’s Head Fritillary (Fritillaria meleagris) which produces beautiful drooping bell shaped flowers in purple and white with an exquisite chequerboard pattern very early in the season.