There are countless lists of plants suggested for septic fields. This is not a comprehensive list, just a list of commonly used plants I feel fairly confident about. Be sure to check your specific septic and site conditions and shade/sun preferences of plants before selecting. Check guidelines for recommended distances for shrubs, vines and trees — there are no guarantees, especially when it comes to trees, shrubs or vines.

For more information, read editor Jim Kneiszel’s Between the Lines column in the April issue of Pumper magazine.

Grasses/Clover (for play fields and heavy usage)

• Traditional lawn (seed or turf)
• Microclover (can mix with eco grasses or meadow flowers)
• Carex pensylvanica (Pennsylvania sledge)
• Eco-grass naturalized lawns/meadows (some are sold specifically for septic field use). Eco-grasses are typically a mix of drought-resistant and clumping grasses like red fescues.

Bulbs/Corms/Rhizomes/Tubers (for naturalizing lawns and meadows)

• allium (all types)
• autumn crocus
• spring crocus
• crocosmia
• bluebell
• gladiolus
• enkianthus
• scilla
• hardy cyclamen
• hyacinth
• ipheion
• iris
• leucojum
• snowdrop
• lilly
• muscari
• narcissus
• tulip (use species ones for naturalizing)

Carpeting/Creeping Perennials ("stepables" for light walking and use. Weeds can be an issue)

• creeping penstemon
• thymes (especially dwarf thyme)
• mazus reptans
• blue star creeper
• aubretia
• armeria (thrift)
• native mosses
• ajuga (dwarf)
• creeping jenny
• hernaria
• baby tears
• brass buttons (hard to establish)
• gold oregano
• carpeting sedums
• carpeting saxifraga

Taller perennial flowers/grasses (For viewing or strolling on paths, it’s best if drainfields are at least 1 foot deep)

• violets
• daylily
• wintergreen
• poppies
• waldsteinia
• anemones
• penstemon (rgl)
• agapanthus
• lady's mantle
• Amsonia
• columbine
• astilbe
• hardy begonias
• foxglove
• bleeding heart
• ferns (most)
• hardy lobelia
• forget-me-not
• sweet william
• creeping woodland phlox
• thalictrum
• tiarella
• toad lily
• aster novae-angliae
• coreopsis
• salvias
• sedums (all kinds)
• irises
• perennial geraniums
• ajuga (tall)
• armeria (thrift)
• false Solomon’s seal
• wild ginger
• Festuca ovina (blue or green fescue)
• deschampsia grass
• pennisetum grass
• stipa tenuissima (feather grass)
• tall fescue grass
• carex grass
• bergenia
• brunnera
• sweet woodruff
• hellebore
• coral bells
• hosta
• primula
• pulmonaria
• saxifraga
• trillium
• yarrow
• artemisia (small, delicate ones)
• liatris
• nepeta

Shrubs (Slow-growing shrubs with fibrous, contained root systems. These are less likely to be a problem if planted at the recommended distances from a drainfield.)

• boxwood
• potentilla
• daphne
• hebes
• dwarf/shrubby euonymus 
•  rhododendron/azaleas
• choisya

Trees with more vertical root growth (Also less likely to cause harm if planted at the recommended distances from a drainfield.)

• cherry
• crabapple
• dogwoods
• genetically dwarf trees
• small species maple: palmatum (Japanese maple)
• maples: griseum, Amur
• cotinus
• cercis
• Japanese snowbell

Wynn Nielsen is a landscape designer on Bowen Island off Vancouver, British Columbia, Canada. This was taken from a handout presented to homeowners at a recent seminar on landscaping over septic systems. Contact Nielsen at www.artistinthegarden.ca.