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Articles by Jim Gainan

As published in the Billings Gazette

Gardening Today: Perennials

Perennials
Perennials are herbaceous plants that die to the ground each fall and come up again each spring. Most perennials are valued in the landscape for their colorful blossoms. Some make excellent cut flowers as well, while others are valued for their foliage that can add color and texture to the garden, such as Silver Mound or the ornamental grasses. there are literally hundreds of varieties of perennials to choose from, with an almost infinite variety of blooming times, color and texture. With just a small assortment of perennials, you can have a variety of color throughout the season.

Perennials can be used in a number of ways in the landscape. They can be used in combination with shrubs and evergreens to provide color and variety. Low, spreading perennials are frequently used as ground covers and in place of mulches to give a greener, warmer feel to an area. A perennial garden can also be created that will provide color throughout the growing season and cut flowers for the home. While perennials cannot rival the season-long color of annuals, the beauty of the individual flowers of many perennials is unequalled and eagerly awaited each year.

  

Soil Preparation
Good soil preparation is the key to success with perennials since they will occupy their spot in the garden for several years. Most perennials prefer a well-drained soil that is high in organic matter. With heavy soils that may drain poorly, you may consider raising the area to improve drainage. For heavy or light soils, incorporating garden compost, well-rotted manure or peat into the top 8 to 12 inches will increase the organic matter and aid in drainage and soil aeration.

 

Mulching
Organic mulches, such as wood chips, compost, shredded bark, or leaves are beneficial in many ways. They help provide a cool, moist soil that perennials prefer, help to reduce weeds and help in overwintering by reducing frost penetration into the soil. For winter, 2 to 4 inch mulch of leaves, cover bark, hay or straw, or compost will provide protection for shallow rooted perennials like mums, shasta daisies, delphiniums, etc.

 

Dividing Perennials
Many perennials benefit from being divided periodically. If permitted to go undivided, they become crowded, loose their vigor and become vulnerable to diseases. Iris, daylilies and lilies are some of the perennials that benefit from being divided about every three years. Other perennials may never need dividing. Consult us if you are unsure as to what varieties need dividing.

 

Designing a Perennial Bed
Designing a perennial bed can be an enjoyable experience. For the beginner, it may seem a bit overwhelming, but keep in mind that if you are not happy with the initial planting scheme, it can always be changed. Obtaining, for the first time, perennials that will give you a good mix of seasonal bloom, color and the proper heights, can be difficult even for the experienced gardener.

It is usually best to start with a plan. Following is a simple plan for a perennial bed that has been designed with lower growing plants in the foreground and taller plants in the back, to provide a long season of bloom and variety of color. Listed are some possible varieties for use in this proposed perennial garden. Other varieties or colors could easily be substituted.

Sun

  1. Peony - Pink
  2. Daylily - Yellow
  3. Siberian Iris - Dark Blue
  4. Rudbeckia Goldsturm
  5. Chrysanthemum - Bronze
  6. Lamb's Ear (Stachys)
  7. Columbine - Mixed Colors
  8. Coreopsis Moonbeam

Shade

  1. Old Fashioned Bleeding Heart
  2. Astilbe Fanal (Red)
  3. Hosta Frances William
  4. Astilbe Bridal Veil (White)
  5. Hosta Royal Standard
  6. Lily of the Valley
  7. Ajuga Bronze Beauty
  8. Bergenia Morning Red

Tall

  1. Daylily - Yellow, red, orange, rose-pink, mahogany. Blooms late Spring to Fall.
  2. Delphinium - Blue, white, violet, pink, purple. Blooms early Summer and early Fall.
  3. Iris, Bearded - White, blue, red, pink, yellow, others. Blooms Spring.
  4. Iris, Siberian - White, blue, purple. Blooms early Summer.
  5. Liatris Rose - Purple, white, bluish purple, pink. Blooms late Summer.
  6. Lilies - White, yellow, orange, pink, red. Blooms Summer.
  7. Lupines - White, pink, blue, red, yellow. Blooms early Summer.
  8. Salvia - Blue, purple, white. Blooms Spring to Fall.

Medium

  1. Aster - Lavender, mauve, pink. Blooms Fall.
  2. Astilbe - White, pink, red. Blooms early Summer.
  3. Baby's Breath - White, pink. Blooms early Summer.
  4. Bee Balm - Pink, red. Blooms Summer.
  5. Bleeding Heart - Pink, ivory. Blooms Spring.
  6. Chrysanthemum - Yellow, red, white, pink, bronze. Blooms Fall.
  7. Columbine - White, yellow, pink, blue, red. Blooms late Spring.
  8. Coreopsis - Yellow. Blooms Summer to Fall.
  9. Dictamnus - White, rose-pink. Blooms Summer.
  10. Ferns - Green foliage. Blooms all season.
  11. Gaillardia - Yellow, red-orange. Blooms Summer to Fall.
  12. Oriental Poppy - White, pink, orange, salmon, mahogany. Blooms Spring.
  13. Peony - White, red, pink, rose, cream. Blooms Spring.
  14. Phlox - Salmon, red, white, pink, red-orange, purple. Blooms Summer.
  15. Sedum Autumn Joy - Pink. Blooms late Summer.
  16. Shasta Daisy - White. Blooms Spring, Summer.

Low

  1. Bergenia - Pink, red. Blooms late Spring.
  2. Snow-on-the-Mountain - White and green foliage. Blooms Summer.
  3. Coral Bells - White, pink, red. Blooms late Spring to early Summer.
  4. Fernleaf Bleeding Heart - Pink, white. Blooms Spring to Summer.
  5. Lily of the Valley - White. Blooms Spring.
  6. Hosta - White, blue, mauve. Blooms Summer to Fall.
  7. Moss Phlox - White, pink, blue, rose-red. Blooms early Spring.
  8. Silver Mound - Silver foliage. Blooms all season.

Stone Crop/Sedum - Yellow, pink, red. Blooms Summer.