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 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 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 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).


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.








Blanket Flower



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
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
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
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
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/
Summer Partial Sun Require fertilizing with Superphosphate or Bonemeal, divide in fall
Platycodon (Balloon Flowers) Blue Medium
Summer Partial Sun Will not tolerate wet soil, does not transplant well, requires staking.
Primula (Primrose) Assorted Low/
Spring Partial Sun Cool, moist, organic soil
Rudbeckia (Cone Flower) Yellow Gold Medium Summer Partial Sun Easy to grow

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