Perennials

Become an expert in Perennials! 

• Become an expert at the classification, identification and culture of Perennial Garden Plants. 
• A course equally valuable to landscapers, nurserymen, cut flower growers and garden enthusiasts.
• Discover what perennials are, which perennial plants are most popular today, their cultural requirements (ie. feeding, watering, soil requirements, pruning, pest control), and learn how to use them to create beautiful landscapes.

Perennials are versatile, beautiful and important to the landscaping industry, as well as the nurseries that grow and supply them. 

Perennials come in all forms, from herbaceous plants that die down in the winter and re-emerge in spring (year after year), to plants that retain their soft-stemmed leafy growth year round. Although beautiful, many perennials are also tough and very much adapted to a variety of climates - ranging from very dry to wet. Some have colourful foliage as well as beautiful flowers, others add architectural interest - but all add excitement and diversity to the landscape or garden as they burst into flower each year.

Lesson Structure

There are 8 lessons in this course:

1. Introduction
   • Review of the system of plant identification
   • Physiology
   • Information sources
2. Culture
   • Planting
   • Staking
   • Mulching
   • Watering
   • Feeding
   • Pruning, etc.
3. Propagation and Hybridization
4. Review of Major Types of Perennials
5. Pests & Disease
6. Irrigation & Hydroponic Culture Techniques
7. Landscaping with Perennials
8. Further Uses.

Aims

• Describe the identification of Perennial Plants
• Determine sources of further information for identifying and growing different varieties of perennials.
• Discuss a variety of cultural techniques used to improve success in growing of different perennial plants
• Determine the propagation of different perennial plants.
• Discuss the horticulture of a range of commonly grown perennial genera.
• Discuss the management of pests and diseases occurring on a range of perennial plants.
• Manage irrigation and drainage to ensure optimum water levels are maintained for healthy growth in perennials.
• Determine appropriate use of perennials in a range of horticultural situations.
• Describe a variety of uses for perennials.

Tips for Gardening with Perennials

A perennial garden is perhaps the ultimate flower garden. Perennials grow fast, are quick to produce flowers, and if you choose the right ones for the right places, can give you an established garden faster than most other types of plants.

When designed and grown well, a perennial garden produces a blaze of colour for many months – starting in spring, flourishing through summer, and beyond into autumn. As one type of flower or foliage finishes, another emerges to give life and colour to the bed.

What is a flowering perennial?
Botanically speaking, a perennial is any plant that lives for more than one or two years. This includes trees and woody shrubs, but most gardeners think of perennials as small flowering shrubs such as geraniums and Margeurite daisies, and herbaceous soft-wooded plants that die back each winter, such as hellebores, campanulas and aquilegias.

Types of Perennial Gardens
Perennials can be used in just about any garden situation, but are most commonly used in flowering borders, rock gardens, cottage gardens, feature beds or tubs.

Secrets of Success
Perennial displays use a great deal of water and nutrients, hence soil conditions need to be the very best at all times. Some do like shade but the majority prefer sunny positions.

Maintenance Tips
Pay attention to the following for best results:
• Soil – because they grow fast, they react faster to adverse conditions. Most grow best in moderately fertile, well-drained soil.
• Feeding – fast growth means heavier demand on nutrients, so attention to feeding and watering is very important. Dig aged compost and manure into the soil before planting and spread blood and bone around the plants in late winter. Additional liquid feeds will boost growth during the warmer weather.
• Pest control – tender soft foliage is generally more attractive to pests and diseases than harder drier tissues, so many perennials are subject to pests and diseases. In particular, watch out for snails and slugs.
• Staking – being tender, the stems of herbaceous perennials are more likely to break in strong wind than woody plants. Bamboo stakes are sufficient for most perennials – taller, spreading plants may need three or more stakes.
• Deadheading – removing dead flowers, fruits and damaged leaves frequently will both keep the plants looking more attractive and minimises pest and disease problems. For most perennials, weekly deadheading in summer is ideal.
• Lift, divide and replant herbaceous perennials in late autumn or early winter, about every three or four years.

Designing a Perennial Display
The aim is to have the plants flowering in a sequence – as one plant emerges, another finishes and is either cut back or dies down. Plants with interesting foliage colours or textures are used as fillers and as contrasts.

For most beds, a three-tiered arrangement is effective:
• Structural plants for height at the back of the bed
• Medium-sized plants in the middle
• Lower-growing border plants in front

In general, plants look better growing in groups, clumps or ribbons. Plant in groups of at least three specimens for each flower type, and preferably more for larger beds.  Aim for a crowded effect, as this will give a better display and will keep down the weeds.

It may take a season or two to work out the best display but if you’re not happy with the effect, most perennials can be easily moved in the cooler weather.

WHAT ABOUT BEHIND?
Put a hedge, large shrubs, fence, or a trellis covered by roses etc as a backdrop to a perennial bed.

PLANTS for PERENNIAL GARDENS

Structural Plants
Delphiniums, Echium, Hollyhocks, Lobelia, Lupins, NZ Flax, Yucca,

Medium Plants
Achillea, Chrysanthemum, Echinacea, Eryngium, Geraniums & Pelargoniums, Geum
 Hosta, Physostegia, Rudbeckia, Salivia

Border Plants
Ajuga, Allium, Erigeron, Helleborus, Pinks, Primrose, Pulsatilla, Saxifraga, Scabiosa,
Viola