Wet soils: plants for

There are many plants which will grow successfully in soils which are permanently moist, but few will survive long spells of flooding or waterlogged conditions, especially in summer. The ones listed here are more tolerant than most.

Liquidambar has impressive autumn colour.
Liquidambar has impressive autumn colour.

Introduction

Air and water are needed for plant roots to support healthy growth. Saturated soils will have insufficient oxygen for healthy root function and may lead to root decay. Fortunately, there are some shrubs and herbaceous

perennials which don’t seem to mind having wet feet.

For mixed extremes, see our list of plants tolerant of both wet and dry soils.

Practical considerations

Preparation for planting

Before planting trees in wet conditions, you may need to improve drainage. On soils prone to wet conditions in winter and drought in summer, such as heavy clays, improve the soil by incorporating bulky organic matter. This should be done over as large an area as possible. Artificial drainage will be necessary if severe waterlogging or flooding is a problem.

Planting

Improve drainage at the base of the planting hole by forking through any compacted soil. Fork through the sides of the planting hole or break down the sides into the planting hole when backfilling. This avoids creating a planting 'bucket' or sump which fills with water: a problem that can lead to poor establishment or the death of the tree. On heavy soils prone to winter wet, protect the finer surface feeding roots by planting trees on a slightly raised mound to improve drainage around the root system and carry out the planting in early spring.

Suitable plants

(*) suitable for acid soils
(e) evergreen
(^) tolerant of wet soils but better suited to moisture retentive well-drained soil
AGM - The RHS Award of Garden Merit

Where only a genus is mentioned, such as Spiraea, all species can be considered. Cultivars of the species listed, such as Hydrangea macrophylla ‘Altona’ are also suitable.

 

Trees

Acer griseum AGM, A. negundo, A. palmatum, A. pensylvanicum, A. rubrum
Aesculus pavia 'Atrosanguinea' AGM
Alnus cordata AGM, A. glutinosa, A. incana 'Aurea', A.× spaethii 
Amelanchier
including Amelanchier lamarckii AGM
Betula nigra (river birch), B. pendula, B. pubescens
Crataegus laevigata, C. monogyna
Frangula alnus (alder buckthorn)
Fraxinus excelsior, F. ornus
Gleditsia triacanthos f. inermis 'Sunburst'
Ligustrum japonicum, L. lucidum (e) 
Liquidambar styraciflua (*)
Magnolia (most) (*) (^)
Mespilus germanica (medlar) (^)
Nyssa sylvatica (tupelo) AGM, N. aquatica (*)
Paulownia tomentosa AGM (^)
Populus alba, P. tremula (poplar)
Prunus (most)
Pterocarya fraxinifolia
Pyrus communis
(common pear)P. calleryana 'Chanticleer', P. salicifolia 'Pendula' AGM
Quercus palustris (pin oak), Q. robur (common oak)
Salix (willow) including S. alba var. vitellina 'Britzensis' AGMS. babylonica var. pekinensis 'Tortuosa',
S. daphnoides, S. gracilistyla 'Melanostachys' AGM, S. × sepulcralis var. chrysocoma AGM, S. × sepulcralis 'Erythroflexuosa' AGM
Sambucus nigraS. racemosa
Sorbus aucuparia (mountain ash)
Tilia (lime)
Zelkova serrata AGM, Z. × verschaffeltii

 

Conifers

Abies alba (silver fir), A. koreana AGM (Korean fir), Abies procera (noble fir) (*) (^)
Chamaecyparis lawsoniana, C. obtusa, C. pisifera (*) (^)
Ginkgo biloba AGM (^)
Metasequoia glyptostroboides (dawn redwood) AGM, M. glyptostroboides Goldrush = 'Golden Oji' AGM (^)
Picea abies, P. glauca, P. omorika AGM, P. orientalis AGM, P. pungens (*) (^)
Pinus sylvestris
Pseudotsuga menziesii AGM 
Sequoia sempervirens AGM
Taxodium distichum (swamp cypress) AGM (*)
Thuja occidentalis (white cedar), T. plicata (western red cedar) 
Thujopsis dolabrata (^)
Tsuga canadensis (Eastern hemlock), T. heterophylla AGM

 

Shrubs for acid soils (chalk haters)

Andromeda polifolia (*)(e)
Arctostaphylos uva-ursi 'Vancouver Jade' (*)(e)
Aronia arbutifolia 'Erecta' (*)
Clethra alnifolia (*)
Enkianthus campanulatus AGM (*)(e), E. cernuus f. rubens AGM (*)
Erica tetralix (*)(e)
Gaultheria procumbens AGM (*)(e), G. shallon (can be invasive) (*)(e)
Kalmia angustifolia AGM, K. polifolia (*)(e)
Ilex verticillata (*)
Lindera benzoin (*)
Myrica gale (*)
Rhododendron hippophaeoides (e)(*), R. viscosum (*)
Vaccinium myrtillus (bilberry) (*), V. vitis-idaea (*), V. corymbosum (blueberry) (*)
Zenobia pulverulenta (*)

 

Evergreen shrubs

Berberis stenophylla AGM (e)
Magnolia grandiflora (e)
Phyllostachys (bamboo) (e)
Pseudosasa (bamboo) (e)
Sasa (bamboo) (e)

 

Deciduous shrubs

Calycanthus floridus, C. occidentalis
Cornus alba,
C. florida, C. sericea
Diervilla × splendens
Hippophae rhamnoides
Hydrangea macrophylla, H. paniculata
Kerria japonica 'Pleniflora' AGM
Leycesteria formosa
Neillia thibetica
Photinia villosa
Physocarpus opulifolius 'Diabolo'
Prunus spinosa (blackthorn)
Rubus arcticus
Salix repens
Sambucus nigra
Sorbaria
Spiraea
Symphoricarpos
Viburnum opulus
Weigela
Wisteria floribunda, W. sinensis

 

Herbaceous perennials

Acorus gramineus ‘Ogon’
Actaea
Astilbe
Caltha palustris
Cardiocrinum cordatum var. glehniiC. giganteum
Darmera peltata AGM
Dodecatheon meadia AGM, D. hendersonii AGM
Euphorbia griffithii, E. sikkimensis AGM
Filipendula ulmaria
Gunnera manicata
Hesperantha coccinea 'Sunrise’ AGM
Hosta
Iris ensata ‘Rose Queen’ AGM, I. laevigata, I. pseudacorus, I. sibirica ‘Tropic Night’ AGM
Ligularia przewalskii
Lilium pardalinum AGM, L. superbum
Lobelia cardinalis AGM
Lysimachia nummularia, L. punctata
Lythrum salicaria
Mimulus luteus, M. primuloides, M. ringens
Monarda didyma
Primula denticulata AGM, P. japonica
Trollius
Zantedeschia aethiopica

 

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