If you are lucky enough to have an area of your garden with damp conditions, then here are my suggestions for some of the very best native wetland plants that will add lots of colour and structure, while attracting a host of wildlife too.
- Purple loosestrife (Lythrum salicaria) – this is a simply stunning perennial, with spires of intense magenta flowers that attract insects throughout the summer. In damp soil it will grow up to 1.5m high, but it is very adaptable and able to thrive in sunny garden borders too, in all but the driest soils. There are several garden cultivars of purple loosestrife, some with paler pink flowers and more compact growth. These seem to attract insects for nectar too, but might not provide the same value as a food plant for several moth species as our native purple loosestrife – no garden should be without it!
- Angelica (Angelica sylvestris) – a statuesque umbellifer, growing up to 2m high in sun, or in all but the deepest shade. From July to November its pink and white flowers offer plenty of nectar to hoverflies and other insects. This plant is the source of crystallised angelica, once commonly used for cake decoration, but if you leave the architectural silhouette of the hollow stems through the winter, you are also preserving lots of safe hibernating spaces for insects too.
- Devil’s bit scabious (Succisa pratensis) – with vibrant blue flowers from June to September, this is the only scabious that thrives in damp conditions. However, like all scabious, its rich supply of nectar is irresistible to butterflies and moths. A slender and delicate beauty, it is worth centre stage, near a path or pond edge where you can enjoy it close to. And why the strange name? Apparently this is because the thick root ends abruptly, so it was thought that the devil had bitten this off beneath the soil!
- Lady’s smock (Cardamine pratensis) – also known as ‘cuckoo flower’ and milkmaids’ because it flowers in spring, this is another delicate beauty whose pale pink flowers give a tapestry-effect through wet meadows. Plant it in sun or light shade and enjoy attracting Orange Tip and Green Veined White butterflies into your garden – it is an important food plant for both larvae and adults. Allow this plant to seed naturally and you will soon have small drifts of colour all through the spring.
- Marsh marigold (Caltha palustris) – an early spring arrival and a real dazzler, with large, glossy, golden yellow flowers like giant buttercups, cheering up even those chilly days from early April onwards. They can cope with sun or moderate shade, and damp soil to shallow water too. Dead-heading will extend the flowering season into the summer, when the plants can be easily divided, otherwise try propagating from the large seeds.
Please avoid the double form, called ‘Plena’ or ‘Flore Pleno’, which is often sold in garden centres – like most double flowers, this will not offer the same nectar supply for insects.
- Ragged robin (Lychnis flos-cuculi) – with open, ragged-looking pink petals and branching red stems, ragged robin always seems to be a favourite. There is a naturally occurring white-flowered form too. This is a very versatile plant, successful in many situations except the driest soils, and drifts of plants in amongst a damp border or on a pond edge will give months of pleasure for you and nectar for a range of insect visitors. Easily propagated from saved seeds.
- Marsh woundwort (Stachys palustris) – easily one of my favourites, this robust plant will form clumps of elegant pinkish purple spires up to a metre high, flowering from June until the first frosts. This is a very useful late nectar plant for bees and a larval food plant too. It naturally loves ditches, swamps and fens, but is a stunning garden plant, as long as the position you give it isn’t too dry.
- Meadowsweet (Filipendula ulmaria) – growing in clumps, with ‘frothy’, creamy white flowers, this makes a wonderful sight in damp soils. It has a wonderful honey fragrance too, and was one of the medieval ‘strewing herbs’ used to disguise bad smells in houses! It is a very good late nectar source for hoverflies and bees and is the food plant of some wonderfully-named moths, such as the Powdered Quaker and the Hebrew Character. Meadowsweet will suffer from mildew if the soil conditions are dry, but, when growing happily in damper soils, you might occasionally need to manage its sideways growth unless you have plenty of space.
- Guelder rose (Viburnum opulus) – a stunning shrub to join the list, guelder rose is our native viburnum that loves damper soils but really isn’t fussy about average garden conditions too. Growing up to 4m, it provides masses of white flowers in late spring, that attract hoverflies and other insects, followed by clusters of bright red berries that will attract lots of hungry birds like bullfinches into your garden to feast through the winter.
Those with smaller gardens don’t need to miss out – there is a garden cultivar – Viburnum opulus ‘Compactum’ which grows to about 1m and still offers those stunning berries and autumn leaf colours.
As autumn gives way to winter these plants will all have finished flowering, but don’t rush to ‘tidy’ them by trimming back. Not only do many of the dried stems look wonderful through winter, especially when edged by frost, but they also provide important shelter for wildlife during colder conditions. Wait until late winter before you trim back old growth in preparation for spring.