Plants for wet soils

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The main problem for gardens with constantly wet soils is that they often lack oxygen, which in turn leads to the suffocation of the plant's root-system.

To overcome this there are plants that can be chosen which benefit and flourish in such soil conditions and normally these plants are those found growing close to, or even in water itself.

Plants to use

Salix (Willow) in both its tree and shrub forms which tolerates a high level of water content, as does the tree Alnus (Alder).

Taxodium (Swamp Cyprus) makes a handsome tree with attractive foliage and bold bronze Autumn tints. The roots of this deciduous conifer are specially adapted for living in water.

The many forms of Sambucus (Elder) can offer a range of leaf colours and some with an interesting cut-leaved effect.

Herbaceous (Perennial) plants offer by far the widest choice of plants and many grow best in such planting positions, and come up year after year.

The giant rhubarb-like leaves of both Gunnera manicata and Rheum palmatum are good examples and look as if they belong in some tropical rainforest, but beware, these take up a great deal of space.

Not so large-leaved but equally attractive, are the numerous varieties of Hosta with both flowers and foliage of interest. Flowers are also not forgotten with the humble Iris pseudocorus (Flag Iris) and the noble Lobelia cardinalis 'Queen Victoria' with its deep purple foliage showing off the bright dark red flowers during mid Summer.

Astilbes, when planted in bold drifts or as single specimens give bold patches of late Spring early Summer colour to follow those of the Caltha palustris (Bog Marigold) in its yellow, white and double flowering forms.

A gay bold Summer display is offered by Mimulus luteus (Monkey Flower) with a range of bright, boldly coloured flowers. It would be wrong not to mention the many varieties of Ligularia with either large daisy-like flowers or bold elegant upright spikes.

No wet land planting would be complete without the large yellow or white spath-shaped flowers of Lysichiton but do not touch either the flowers or the 1m (3ft) high light green cos lettuce-like foliage or you will find out why it is called the 'Skunk Cabbage'!

Many grasses and some ferns such as Osmunda regale (Royal Fern) add structure and shape to the planting.

Planting

Establishing plants in a wet environment can sometimes be difficult because it is a fine balance between too much water when the plants are young and too little once they are established.

Excess water can kill fragile plants in the Winter and early Spring so whenever possible plant in mid to late Spring.

Drainage improvement

	Raising the planting soil level a few centimetres (inches) above the surrounding surface, using good quality garden soil and organic material, can greatly assist survival.
	During the wet days of winter, digging shallow drainage channels around the outer edge of planting areas will allow any surplus water to drain away freely.

Winter protection

Frost and cold can also cause damage and mulching with a 5cm (2in) layer of organic material such as well-rotted farmyard manure, spent mushroom compost, garden compost or a proprietory planting compost often protects the plants during bad weather.

Feeding

All water-loving plants are hungry feeders, so applying a general fertilizer each Spring will help to produce bushy strong-growing and flowering plants.