Plant Selection for a Shady, Wet Site
A client has a 500 sq ft area on the north side of their house that is consistently moist due to poor drainage and receives only 2-3 hours of morning sun. The soil is heavy clay with a pH of 6.5. The client wants a low-maintenance garden with year-round interest, including evergreen structure, flowers, and fall color. They are allergic to bee stings and prefer to avoid plants that attract many bees. The area is in USDA Zone 6. The budget is $3,000 for plants and soil amendments.
1. Recommend a planting plan with specific plant species that meet the site conditions and client preferences. Explain your choices.
Read the worked answer
For a shady, moist clay site in Zone 6, choose plants tolerant of wet feet and low light. Evergreen structure: Inkberry holly (Ilex glabra) 'Compacta' (native, evergreen, tolerates wet clay, no significant bee attraction). Add Japanese holly (Ilex crenata) for texture. For flowers and fall color: Fothergilla (Fothergilla major) has fragrant spring flowers, excellent fall color, tolerates wet soil, but does attract some bees; consider 'Mount Airy' dwarf. Virginia sweetspire (Itea virginica) 'Henry's Garnet' has white flowers, brilliant fall color, tolerates wet, but attracts bees; use sparingly. For bee avoidance, choose wind-pollinated plants like grasses: Pennsylvania sedge (Carex pensylvanica) as groundcover, and Japanese forest grass (Hakonechloa macra) for texture. Add Christmas fern (Polystichum acrostichoides) and cinnamon fern (Osmunda cinnamomea) for evergreen and texture. For flowers, use Astilbe (shade, moist, but attracts bees) or Hosta (foliage interest, some flowers attract bees). To minimize bees, focus on foliage and non-flowering plants. Use Hosta 'Sum and Substance' for large leaves, and Heuchera (coral bells) for color, though they attract some bees. Consider dwarf conifers like Chamaecyparis pisifera 'Filifera Aurea' for evergreen. Amend clay with compost (2-3 in) and install raised beds if drainage is poor. Budget: plants ~$2,000, soil amendments ~$1,000.
2. How would you improve the soil drainage and pH to support these plants, and what maintenance tasks would you schedule?
Read the worked answer
Improve drainage by adding organic matter: incorporate 3-4 inches of compost into the top 8-12 inches of soil. If drainage is very poor, install a French drain or create raised beds 6-8 inches high. Test soil pH: 6.5 is suitable for most plants, but if specific plants need lower pH (e.g., inkberry prefers 4.5-6.0), add elemental sulfur or aluminum sulfate to lower pH gradually. However, 6.5 is acceptable for many. Maintain mulch (2-3 inches of pine bark) to retain moisture and suppress weeds. Maintenance: spring cleanup, prune evergreens in late spring, divide perennials every 3-5 years, replenish mulch annually, monitor for pests and diseases. Water during dry spells, especially newly planted. Avoid fertilization high in nitrogen to prevent excessive growth and bee-attracting flowers.