Wet or Dry Conditions

Most of this information is courtesy of Heidi Hesselein of the Pleasant Run Wholesale Nursery given at the September 2006 club meeting.

Plants can suffer from lack of moisture even when rainfall is abundant. Moisture stress can be a constant problem when root growth is limited by concrete or asphalt, when plants are grown in containers or in excessively well-drained sandy soil. When rainfall is below average, supplemental water should be given. Generally, 1 inch of water per week should be adequate.

As you know, the soil may be improved by adding organic matter that will help retain moisture in the soil and mulching will help by reducing evaporation of water from the soil surface as well (as keeping weeds in check). However, if plants seem to constantly dry out--in spite of your best efforts--you may want to consider growing plants that can withstand dry conditions. Using drought resistant plants may help reduce the water bill and the time you or your client spends working in the garden!

	name	common name (if any)	name	common name (if any)	name	common name (if any)
WOODIES
	Arctostaphylos uva-ursi	Bearberry	Caryopteris spp	bluebeard	Cotinus coggygria	Smoke tree
	Hamamelis x intermedia	Witch-hazel	Hamamelis vernalis	Vernal Which-hazel	Lonicera spp	Honeysuckle
	Rhus spp	Sumac	Sarcococca hookeriana	Himalayan Sarcococca	Spiraea x vanhouttei
	.Taxodium distichum	Bald Cypress	Viburnum rhytidophyllum	Leather Leaf Viburnum	Xanthorhiza simplicissima	Yellowroot
	Buddleia species	Butterfly bush	Cephalotaxus harringtonia	Japanese plum yew	Cotoneaster spp.
	Hamamelis virginiana	Which-hazel	Hypericum spp.	St. John's Wort	Myrica pensylvanica	Bayberry
	Rosa rugosa	Rugosa Rose	Spiraea x bumalda	Anthony Waterer Spiraea	Taxodium ascendens	Bald Cypress
	Viburnum dentatum	Arrow-wood Viburnum	Viburnum x rhytidophylloides		Yucca spp.

PERENNIALS
	Achillea Asclepias	Yarrow	Ceratostigma		Dianthus	Pink
	Gaura		Hemerocallis	Daylily	Lavandula	Lavender
	Muhlenbergia	Lindheimer's muhlygrass	Pennisetum		Polygonatum	Solomon's seal
	Schizachyrium	Little bluestem	Veronica	Speedwell	Agastache rupestris	Licorice Mint Hyssop
	Aster		Coreopsis		Echinacea	Coneflower
	Gaillardia	Blanket flower	Heuchera	Coral bells	Liatris	Gay feather
	Nepeta	Cat mint	Penstemon		Rudbeckia
	Sedium		Amsonia		Baptisia
	Cortaderia	Pampas grass	Epimedium		Geranium
	Iberis	Candy tuft	Liriope	Lily turf	Ophiopogon	Mondo grass
	Perovskia	Russian sage	Salvia		Sempervivum
	Artemesia		Calamintha		Delospenna
	Euphorbia		Helictotrichon	Blue Oat Grass	Kniphofia	Torch Lilies
	Miscanthus		Panicum		Platycodon	Balloon flower
	Santolina	Lavender cotton	Stachys	Lamb's ear

Most plants do not like to have their roots wet for an extended time. Plant roots need oxygen and the longer the roots are saturate the more difficult it becomes for the plant to survive; however, some species can adapt better than others to fluctuations in soil moisture or tolerate extended periods of flooding. Some factors to consider when planting are:

Duration: Many plants can withstand temporary flooding if standing water only persists only a few days. If sites are flooded longer or more frequently, you need plants that are specially adapted to these conditions.

Soil Type: Plants growing in sandy or light soils that are wet but drain quickly are less likely to be damaged than those growing in heavy clay soils.

Season: Plants are better to withstand flooding in spring and summer than in the fall and winter. It is not unusual for foliage on a plant that has been under water to turn brown but, as a general rule, this does not indicate any permanent damage.

The following is a list of some woodies and perennials that will naturally thrive in a wet site.

	name	common name (if any)	name	common name (if any)	name	common name (if any)
TREES
	Amelanchier	Service berry	Betula nigra*	River birch	Magnolia virginiana*	Sweet bay magnolia
	Nyssa sylvatica*	Black gum	Clethra alnifolia*	Summer sweet	Asimina triloba*	Paw paw
	Liquidambar styraciflua	Sweet gum	Metasequoia glyptostroboides	Dawn redwood	Taxodium distichum*	Bald cypress

SHRUBS
	Aesculus parviflora	Bottlebrush buckeye	Calycanthus floridus*	Carolina allspice	Fothergilla gardenii	Dwarf Fothergilla
	lex glabra	Inkberry	Itea virginica	Virginia sweet spire	Physocarpus opulifolius*	Eastern ninebark
	Vaccinium corymbosum*	High bush bluberry	Viburnum nudum		Viburnum trilobum	American Cranberrybush
	Aronia arbutifolia*	Red chokeberry	Chionanthus virginicus	Fringe tree	Cornus alba*	Dogwood
	Hamamelis vemalis	Vernal witchhazel	Ilex verticillata*	Winterberry	Potentilla fruticosa	Bush cinquefoil
	Myrica pensylvanica	Bayberry	Viburnum dentatum	Arrow-wood	Viburnum opulus	European cranberry bush
	Xanthorhiza simplicissima	Yellowroot

PERENNIALS
	Aconitum	Monkshood	Amsonia tabemaemontana	Willow amsonia	Astilbe sp.
	Chelone Dicentra sp.	Turtle head	Filipendula sp.	Meadowsweet	Hibiscus moscheutos*	Common rose mallow
	Ligularia sp.*	Golden-ray	Polemonium reptans	Creeping Polemonium	Rodgersia	Rodger's flower
	Alchemilla mollis	Ladie's mantel	Aruncus dioicus	Goat's-beard	Brunnera macrophylla	Heart-leaf Brunnera
	Cimicifuga racemosa	Snake root	Eupatorium purpureum	Bluestem Joe-pye-weed	Hemerocallis sp.	Daylily
	Iris ensata*		Monarda didyma*	Bee-balm	Polygonatum sp.	Soloman-seal
	Tiarella sp.	Foam flower

FERNS
	Athyrium filex-femina	Lady fern	Matteuccia struthiopteris	Ostridge fern	Osmunda regalis	Royal fern
	Dryopteris celsa	Log fern	Osmunda cinnamonea	Cinnamon fern