Perennials: General Planting Instructions

The garden area should be dug to a depth of 12″-18″ with one-fourth of the area being organic soil amendments such as peat moss or leaf mold from your compost pile, composted barnyard manure, composted bark or any combination of these. For each 100 sq. ft. of garden space, use 5 lbs. of Plant-tone (a slow-release, all-organic fertilizer), rock phosphate (encourages flowering), 5 lbs. gypsum (a soil conditioner; especially for clay soil) and 2 lbs. of 8 month Osmocote fertilizer.

Most plants should be spaced from 18″-24″ apart depending on the size and height of the mature plant. Smaller plants which only grow to 12″-15″ in height can be planted 12″ apart.

A pine bark mulch of 3″ is fine for most plants to conserve moisture during the summer (Tall Bearded Iris and Peonies should not be mulched near their stems so as to avoid root and crown rot). An airier winter mulch of 5″-8″ of straw, composted leaves, pine boughs or salt hay is put on after the ground has frozen, usually in December, and removed in late February before the plants break dormancy. This keeps plants from heaving as the ground freezes and thaws.

When transplanting or dividing, consider this rule of thumb; do spring flowering plants in the fall or after bloom; do fall blooming plants in early spring or after bloom. It is usually best to cut the foliage back when transplanting or dividing so that the plant’s energy can be directed to the roots instead of the foliage. Container perennials, such as you receive from the Retail Mail Order or our Garden Center, can be planted just they are. Keep the plants in the shade and the roots moist until planted in the garden. If your container plant is extremely pot-bound, use a sharp knife and cut off the bottom 1/2″ of the roots and soil and “score” the sides of the compressed soil. This releases the roots and enable them to spread out properly. Water deeply and mulch immediately after planting.

For general garden maintenance, be sure to water slowly and deeply for 4-6 hours in the same area every 7-15 days–an application of 1″-2″ per watering a penetration depth of 12″-18″. Weed weekly as needed.

Drought and Heat Tolerant

Provide these plants with a permanent mulch in the summer to retain as much moisture as possible. Water deeply, but infrequently and fertilizer sparingly.

  • Achillea ‘Moonshine’, ‘Coronation Gold’
  • Artemisia ssp.
  • Baptisia australis
  • Coreopsis ssp.
  • Dianthus grat.-Cheddar Pink
  • Eryngium-Amethyst Sea-Holly
  • Gaura lindheimeri
  • Helictotrichon semp.-Blue Oat Grass
  • Hemerocallis-Daylily
  • Iris Siberica-Siberian Iris
  • Iris germanica-Tall Bearded
  • Rudbeckia ssp.
  • Liatris spicata-Gayfeather
  • Nepeta-Catmint
  • Oenothera ssp.
  • Perovskia atrip.-Russian Sage
  • Platycondon grandiflora-Japanese Ballon Flower
  • Salvia ‘Blue Queen’, ‘Ost Friesland,’ ‘May Night’
  • Sedum-stonecrop
  • Stachys-Woolly Lamb;s Ear
  • Thyme and Origanum (herbs)
  • Yucca

Long-Blooming Perennials

  • Achillea-3 months
  • Armeria-2 months
  • Aster Frikarti-4 months
  • Buddleia (shrub)-4 months
  • Campanula carpatica-3 months
  • Ceratostigma plumb.-3 months
  • Chrysogonum-4 months
  • Coreopsis verticillata-4 months
  • Coreopsis lanceolata-2 months
  • Coreopsis grandiflora-2 months
  • Dicentra eximia-4 months
  • Echinacea-3 months
  • Echinops-2 months
  • Gaillardia-3 months
  • Gaura-4 months
  • Geranium ‘Prostratum’-5 months
  • Gypsophila-2 months
  • Heliopsis-3 months
  • Hemerocallis-(everblooming and reblooming cultivars)-up to 4 months
  • Hibiscus moscheutos-2 months
  • Lysimachia clethroides-2 months
  • Lythrum salicaria ‘Robert’, ‘Morden’
  • Pink’, ‘Morden Gleam’-2 months
  • Monarda-3 months
  • Potentilla fruiticosa-4 months
  • Myosotis palustris-2 months
  • Nepeta-3 months
  • Perovskia-4 months
  • Phlox paniculata-3 months
  • Rudbeckia ‘Goldsturm’-4 months
  • Rudbeckia speciosa-4 months
  • Salvia superba-3 months
  • Saponaria officinalis-5 months
  • Sidalcea-2 months
  • Sisyrinchium bermudianum-2 months
  • Stokesia-3 months
  • Tradescantia-2 months
  • Verbena canadensis-5 months
  • Veronica-3 months

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