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The Joy of Perennials

The Joy of Perennials

A perennial is a herbaceous (soft and fleshy) plant that thrives for three or more years. Perennials come in a variety of sizes, shapes and colours and can bloom from early April until late October. For these reasons, they are fast becoming more popular. Perennials are one of the easiest plants to grow. Sun or shade, clay or loam, there is a perennial for almost all of your garden needs.

PLANNING

Planning is an essential part of having a perennial garden. Gardens that are not planned usually have no direction and often are a jumble of colour.
When planning a garden, many factors determine the shape of your garden; from which angle you will view your garden; whether the garden will be informal or formal, and the type of planting (bed or border) you want.
Once the beds and type of garden are decided then its time to choose the types of plants you need. Some factors to consider are light and soil requirements, plant height, time and length of flower, and flower colour. Other factors may be plant fragrance, suitability of plants for fresh cut or dried flowers, and the plants form and texture.
Once all the factors are considered, then it is time to lay out your garden on paper. From a detailed plan, one can see how the garden will look.

BED PREPARATION

Bed preparation is one of the most important aspects in having a successful perennial garden. First, the bed should be dug to a depth of one foot. Next, one should decide what type of soil you have.
For clay soils, 10 to 15 cm of sand and peat moss should be added so the soil can drain properly. Adding gypsum (11 kg per 100 sq. ft.) helps break down the clay. If necessary, garden sulphur can be added to lower the acidity of the soil.
For sandy soils, add 10 to 15 cm of organic material (peat moss, manure, compost) to the soil to hold the moisture in the ground. When adding an organic material, also add a high-nitrogen fertilizer (urea 33-0-0) to help the material break down.
For peaty soils, add horticultural lime to raise the alkalinity of the soil, if necessary.
Finally, an all purpose fertilizer should be worked into the soil. A top dressing of mulch will keep the moisture in and the weeds out.

PLANTING

Planting perennials is a simple task, but the importance should not be overlooked.
There are two stages (dormant and active) in which perennials can be planted. Dormant plants are usually planted in the fall and active plants in the spring and summer.
Planting is a simple task. With a trowel, dig a hole slightly larger than the container in which the plant came. Place the plant in the hole at the same depth as the container (Remember to remove the container). Once in, firm the soil around the plants. Plants should then be watered in with a transplant fertilizer (high in phosphorous).

CARE

Perennials are relatively easy to care for, but they are not maintenance free. Watering, fertilizing, mulching and dividing are some of the tasks involved with the care of perennials.
Fertilizing should be done three times per year (spring, summer and fall) with an all-purpose granular fertilizer. Some perennials need more nutrients during the year and a water soluble general fertilizer should be applied. Watering of newly planted perennials should be done on a regular basis. More established plants should be watered only when there is a dry spell.
Bark, cocoa bean, needle and leaf mulches are some of the mulches used to cover perennials for the winter. Mulching can increase the survival rate of plants through the winter. Mulches provide a weed barrier as well as keeping moisture in the ground.
The dividing of plants is done for three reasons: to control size, to rejuvenate plants, and for the propagation of plants. Dividing is done in the spring and summer. When dividing in the spring, just divide those varieties that bloom in the summer and fall. Only those varieties which bloom in the spring should be divided in the summer.
A perennial garden can provide the homeowner with much enjoyment. Cut and dried flowers, perfumed scents and blooms from April to October are some of the rewards of growing perennials. With a little effort, one can enjoy a garden that blooms and grows for many years.
 
  • Hosta

  • Coneflower

  • Delphinium

  • Blanket Flower

  • Columbine

Popular Perennials

The following is a comprehensive list of the most popular perennials. This list is arranged in alphabetical order, according to genus. Use the information provided, to plan your garden.

Plant Name

Bloom Colour

Pant Size

Bloom Period

Exposure

Comments

Achillea (Yarrow)

Yellow-gold

Any

Mid-Late Summer

Full Sun

Well drained soil, may require staking

Alyssum (Basket of Gold)

Yellow

Low

Early Summer

Partial Sun

Well drained soil, divide in spring

Aquilegia (Columbine)

Blue Purple Yellow

Medium

Late Spring - Mid Summer

Sun/Shade

Well drained soil, divide late summer

Armeria (Thrift)

Purple Rose

Low

Late Spring - Mid Summer

Full Sun

Dry, infertile soil, divide every 4 years

Artemisia (Silvermound)

Silver Foliage

Low

Full Sun

Will adapt to poor soil conditions

Aster

Rose Violet Pink

Medium

Late Summer

Full Sun

Water generously in well drained soil

Astilbe

Pink Red White

Medium

Summer

Partial Sun

Moist, fertile, organic soil

Convallaria (Lily of the Valley(

White

Low

Spring

Sun/Shade

Berries are poisonous

Chrysanthemum Maximum (Shasta Daisy)

White

Medium

Summer

Partial Sun

Fertile soil, divide every-other spring

Chrysanthemum (Hardy Mums)

Red Yellow Bronze

Medium
/Short

Fall

Partial Sun

Well drained moist soil, may transplant in fall

Delphinium

Pink White Blue

Tall

Summer

Full Sun

May require staking, cut back flowers after flowering

Dianthus (Carnation)

Pink Red Rose White Yellow

Medium
/Tall

Late Spring - Summer

Full Sun

Well drained alkaline soil

Dicentra (Bleeding Heart)

Pink to Fuscia

Medium

Late Spring - Late Summer

Partial Sun

Fertile soil, divide in spring or fall

Gaillardia (Blanket Flower)

Red Orange Yellow

Medium

Summer

Full Sun

Light, well drained soil, divide in spring

Gypsophila (Baby's Breath)

White

Any

Mid Summer

Partial Sun

Well Drained, low nutrient, high pH soil

Hemerocallis (Day Lily)

Yellow Cream Bronze Pink

Medium

Late Spring

Partial Sun

Well drained organic soil, divide every 4 to 6 years

Hollyhock

Pink White Red

Tall

Late Summer

Full Sun

Well drained soil, may require staking

Hosta (Plantain Lily)

Lavender White

Medium

Summer

Partial Sun

Organic Soil

Iris

Assorted

Low
/Tall

Spring - Mid Summer

Full Sun

Divide rhizomes after flowering

Lillium (Lily)

Assorted

Tall

Summer

Partial Sun

Fertile soil

Lupimus (Lupine)

Assorted

Medium

Spring

Partial Sun

Cool, moist areas, acidic soil

Paeonia (Peony)

Assorted

Medium
/Tall

Spring

Full Sun

Shade inhibits flowering, establishment time, 3 years

Papaver (Oriental Poppy)

Scarlet Salmon

Medium

Early Spring

Full Sun

Well drained soil, difficult to transplant

Phlox Paniculata (Garden Phlox)

Assorted

Low/
Medium

Summer

Partial Sun

Require fertilizing with Superphosphate or Bonemeal, divide in fall

Platycodon (Balloon Flowers)

Blue

Medium
/Tall

Summer

Partial Sun

Will not tolerate wet soil, does not transplant well, requires staking.

Primula (Primrose)

Assorted

Low/
Medium

Spring

Partial Sun

Cool, moist, organic soil

Rudbeckia (Cone Flower)

Yellow Gold

Medium

Summer

Partial Sun

Easy to grow

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