CONIFERS

EXPAND YOUR KNOWLEDGE OF GROWING CONIFERS

• Learn to identify and grow hundreds of conifers
• Course developed by John Mason (author of "Growing Conifers", with experts fro Australia and England
• For nurserymen, landscapers, gardeners or passionate amateurs seeking to expand and deepen their plant knowledge

Tips for Growing Conifers

Conifers tend to originate in mountainous zones of the world. As such they have a reference for clean non-polluted air. The gardener in such a location has an advantage.

For the gardener who does not live in ideal locations, then a few steps will help in growing your conifers:

• allow plenty of space between plants to maximise ventilation
• do not locate conifers near the driveway or where cars park or idle
• reduce the use of any products that increase air pollution

Sloped land tends to have more air movement at ground surface than flat land. This feature could be utilised to help conifers grow better by aiding ventilation.

Soil

Conifers prefer most well drained fertile soils. Excessively sandy or clay soils are generally not liked by most.

If establishing conifers on a clay based soil it is important to raise the level of soil, by either importing fresh soil onto your property or by adding bulk to the existing soil (ie adding compost). Both methods should treat the existing soil first with gypsum powder to be dug into the clay or a liquid solution (eg. 'Clay Breaker') which is liberally applied to the soil. It is imperative to get the root system above the established water table. For this reason raised garden beds should be about 30cm minimum high. Sloped land will aid drainage, but may actually impede water penetration as most rainfall will just wash over the surface and travel downhill.

Water

Conifers are best kept moist but never wet. Exception to this rule includes the swamp cypress (Taxodium distichum).

Allowing the root zone to dry out may increase sunburn damage due to the dehydration effect on the plant.

Most conifers handle the occasional dry spell well but should never be subjected to drought. Newly planted specimens should be well watered until established. It is important that young evergreen conifers receive adequate water during autumn as a dry root system in winter may be disastrous.

When watering by irrigation it is best to water in such a manner as to avoid excessive wetting of the foliage. Applying water directly to the roots, by drip irrigation or low-riser sprinklers, is regarded as a better watering technique compared to overhead watering. Wet foliage may lead to increased humidity and decline in conifer health.

Mulching

Mulching helps to trap moisture in the soil thereby reduces the chances of drought symptoms. Additionally, watering combined with mulching will lower the soil temperature making it more conducive to conifer growth especially in the hot summer months. Mulch during winter aids in keeping freezing temperatures away from the roots.

Mulch is best kept at a depth of 10-15cm deep. It should not be in direct contact with the base of the trunk as this may increase the chances of collar rot or similar diseases. Mulch material may include pine leaves, bark chips, straw bales, pebbles, etc. Organic mulches help to improve the soil condition over time and provide small amounts of nutrient. Inorganic mulches do not add nutrient value but still conserve moisture and cool the soil.

On a sloped site, mulching will also aid rainfall and irrigation to penetrate into the soil. This also reduces the occurrence of possible erosion on such slopes.

Fertiliser

Conifers generally have a low fertility requirement. Over fertilising may cause either excessive weak growth or toxic burn. Best recommended fertilisers include organic based composted material such as compost, leaf mould or well-rotted manures.

pH

pH refers to the acidity and alkalinity of a soil. Some plants prefer acid soils (eg azaleas and camellias) and others alkaline soils (eg many herbs). Conifers are variable. An example of some pH preferred growth ranges are as follows:

• Abies balsamea 5.0-6.0
• Abies excelsa 5.5-6.5
• Abies picea 5.0-6.0
• Chamaecyparis thyoides 4.5-5.0
• Gingko biloba 6.0-7.0
• Juniperus communis 5.0-6.0
• Juniperus virginiana 5.5-7.0
• Larix decidua 6.0-7.0
• Larix laricina 5.0-6.5
• Pinus rigida 4.5-5.0
• Pinus silvestris 5.5-6.5
• Pinus strobus 4.5-6.0
• Pinus taeda 5.0-6.0
• Taxus sp. 5.5-6.5
• Thuja occidentalis 6.0-7.5

Preferred pH means the plants grow best in that range. Growth will still occur outside that range but will not be at optimum level.

Temperature

Most conifers benefit from a fairly uniform temperature fluctuation during the day. Extremes of day and night are locations best avoided. Varieties from cold districts are best located where they can have a prolonged winter dormant period, protected from winds.

Locations exhibiting winter shade, well drained soil and protection from drying winds is a safe guide for new conifer growers.

Consider the temperatures experienced on the site where you wish to plant a conifer. Is it exposed to full afternoon sun? Or is it full sun only in the morning?

Frost and ice damage may occur on evergreen conifers if temperatures are too low for that particular species. Deciduous twigs may also be damaged by heavy snow and low temperatures.

Sunlight

Generally conifers do best in full sun. Winter shade is good for some varieties as discussed above.

Full shade will develop poor foliage coverage and possible tilted growth - the result of phototropism (where a plant grows towards a light source).

Too obtain a full bodied conifer hedge, specimen or topiary, the plant should be in full sun. Sun scorch may occur when temperatures exceed 35^o

Conifers are relatively pest and disease free in cold or temperate climates, though there are still some problems which may arise.

In hot humid climates, diseases can become more of a problem. In the tropics and subtropics, you are far more restricted as to the range of conifers which can be grown, and the way in which they are grown.

Humidity and prolonged warm conditions will tend to promote fungal diseases. The impact of such problems can be reduced significantly by spacing plants (to improve ventilation), and avoiding getting water onto the foliage when irrigating (as much as possible).

General plant health is important to maintain good plant health - 'a healthy tree indicates a healthy garden'. This means that if watering, fertilising, plant selection and all other plant requirements are right, then the plant will be able to fight off most problems (pests and diseases inclusive).

In cases where conifer trees have started to become a little less thrifty, then improvements in general culture need to be looked at. Consider applying a seaweed solution to revitalise the conifer. Keep the water up but avoid over watering. Is the plant in the right climate and getting the right amount of sunshine?.

Lesson Structure

There are 9 lessons in this course:

1. Introduction Gain a thorough understanding of the system of plant identification and review the general characteristics of the Conifer plant group. You will also gain information on contacts (ie: nurseries, seed, clubs, etc) for your future use.
2. Culture Learn about the cultural requirements of growing Conifers. Discover the different peat and disease problems that effect Conifers, planting techniques, soil types and different cultural practices that maximise the growth of Conifers.
   • You will also learn methods for the successful propagation of Conifers from seed collection to grafting techniques.
3. Trees Many conifers fall into this height category. Some of the popular conifers are Chamaecyparis, Juniperus and Thuja. In this lesson you will also learn the valuable skill of how to prune conifers.
4. Common Medium Size Shrubs Many conifers fall into this height category. Some of the popular conifers are Chamaecyparis, Juniperus and Thuja. In this lesson you will also learn the skill in how to prune conifers.
5. Small Shrubs Learn to choose small growing varieties and select prostrate conifers. Learn about their care and how to care for seedlings form starting out up to planting out stage.
6. Australian Native Conifers Become familiar with Australian native conifers Araucaria, Callitris, Podocarpus are three that you will come across. Learn about the importance of environmental zones in Australia and how it can effect plant growth.
7. Rarer Conifers Discover the more rare conifers Hemlocks, Podocarpus, Larches and leaf characteristics of Cephalataxus.
8. Using Conifers Discover using Conifers in ways you never thought of for their rich scented oils, timber products, bonsai, and Christmas trees
9. Landscaping with Conifers Learn about the techniques for creating a landscape design with the use of Conifers. Including site analysis, following a step by step process and a checklist to use for future designs.

Aims

• Distinguish between different types of conifers in cultivation, including twenty-five different genera and fifty different varieties.
• Specify the general cultural requirements of different conifer genera.
• Determine specific cultural requirements for some commonly cultivated conifer species.
• Specify specific cultural requirements for some lesser grown conifers, including any indigenous and uncommon species.
• Determine different commercial applications for conifers in horticulture.
• Prepare a planting design using conifers.

What You Will Do

• Describe the binomial system used for naming plants, using examples of two conifers.
• Distinguish, using labelled illustrations, between different conifer families, including: Pinaceae, Taxodiaceae, Cupressaceae, Podocarpaceae, Araucariaceae and Taxaceae.
• Use a botanical key to identify two different conifer genera.
• Compile a resource information guide for conifers, including scope of operation and contact information (ie: address, phone, fax), for 30 different contacts, including:
  • nurseries
  • clubs/societies
  • product suppliers
  • other organisations
• Prepare a collection of fifty conifers, not collected elsewhere, each including:
  • a photo, drawing or pressed specimen
  • plant names (scientific and common)
  • cultural details
  • uses/applications.
• Propagate five different conifers, using at least three different techniques.
• Determine the preferred soil requirements, for typical conifers, in our locality.
• Prepare a potting media suitable for container growing an advanced conifer, in a tub.
• Explain the planting requirements which are common to most conifers in your locality.
• Explain irrigation techniques appropriate for conifer culture, in your locality.
• Explain the nutrition requirements of two different conifer species, from different families.
• Explain five health problems common to conifers, including identifying features, significance to the plant, and control.
• Describe how to prune two different conifer species, in your locality.
• Determine two routine cultural procedures, to be undertaken in each month of the year, with conifers in your locality.
• Describe ten conifer species, growing in a specified locality, including:
  • plant description
  • preferred habitat
  • propagation
  • growing requirements
  • uses
• Compare the cultural requirements of ten commonly grown conifer species.
• Explain why it is often difficult to grow other plants beneath the canopy of conifers.
• Determine procedures for successfully establishing two specified conifer species on a specific site which you survey.
• Determine any native conifers endemic to your locality or nearby localities.
• Describe the different features of six specific native conifer species, including:
  • plant description
  • natural habitat
  • propagation
  • growing requirements
  • uses
• Describe different features of five specified uncommonly grown conifer cultivars, including:
  • height
  • foliage colour
  • foliage shape
  • preferred site
  • hardiness
  • Determine two different "non standard" propagation techniques, that may be successful in propagating "rare" and uncommonly cultivated conifer species.
• Formulate a schedule of cultural tasks to be undertaken over a twelve month period, to establish new plantings of a conifer species not commonly grown in your locality.
• Determine ten conifer varieties, including at least five different species, suitable for pot culture.
• Determine five conifer varieties suitable for hedging.
• Compare cultural techniques required for growing two specified conifers in containers with growing them in the ground.
• Describe the culture of conifers in different situations, including:
  • as topiary
  • as bonsai
  • as a hedge
  • as a rockery planting
  • as screening
• Determine conifer species which have commercial value as a plantation crop, including:
  • timber
  • essential oils
  • foliage/filler for florists
• Evaluate the use of conifers, in a garden with both conifers and flowering plants, using a supplied checklist of design criteria.
• Evaluate the use of conifers, in a garden which is either all, or predominantly conifers, using a supplied checklist of design criteria.
• Design a conifer garden bed of thirty square meters, which incorporates at least ten different conifer varieties, and satisfies both aesthetic and cultural requirements of a specified site, that you survey.

They can be effectively incorporated into many differing styles of garden including the English traditional sometimes consisting almost entirely of conifers, rockeries (dwarf and ground covers), to Japanese symbolic style gardens where a ragged and worn looking Cupressus is in stark contrast to the serene and ordered nature of the garden. Conifers could also be incorporated effectively in informal or native bush gardens, depending on the species/cultivars chosen. There is a conifer for just about any situation in your garden.

Conifers come in a huge variety of shapes, sizes ranging from large trees to small prostrate ground covers, from rounded forms to upright conical shapes to sprawling types. The height of conifers varies from only 20cm or so for some of the creeping types to the giant Californian Redwoods, hundreds of feet tall.

Although conifers are not renowned for their vast array of colourful flowers, their foliage does come in a large range of colour shades and textures; and the great thing is that these can be used for affect all year round (unlike plants that flower for only a short time and then become another obscure green mass of leaf). Most conifers are cool climate plants and generally have a characteristic resinous fragrance. The majority are evergreens. The foliage of conifers can be short and spiky, or long and needle like. Colour variations range from greens, blue greys, golds and yellows, to purplish bronze and more. Colour may also vary according to the season, for example, new spring growth may be light green or golden yellow which turns darker with age, or the foliage of some might turn purplish or bronze in colour during the cooler months.

A well planned conifer bed can provide colour all year round. One trick is to use a variety of different coloured foliage plants and different shapes planted together so that they contrast one with another.

Using Conifers

Common uses for conifers in a park or garden include:

• for hedging (both low and tall) 
• as topiary specimens
• stand alone specimen trees
• as part of a shrubbery, often as a contrast plant
• low growing or prostrate shrubs as groundcovers or cascading down a slope, over rocks or a    wall
• windbreaks - but be careful with planting distances as many conifers have a tendency to self prune (dropping their lower branches) if planted to close together, which makes them ineffective as a windbreak, as the wind gets funneled beneath the plants near ground level
• as specimens in containers
• as 'Christmas Trees' with suitable varieties kept in containers and bought indoors for a short time during the Christmas period
• dwarf varieties can be used as low borders along a pathway or to delineate a garden bed
• to frame a building or attractive view

• as a windbreak
• as a visual barrier or screen
• to reduce noise (i.e. on the edge of freeways, or if you have noisy neighbours)
• to provide shade
• to provide shelter for animals (e.g. stock on farms)
• to stabilise the soil (i.e. prevent erosion, landslips)
• to provide timber - many conifers are highly valued for this purpose
• to control weed growth (eg. needles dropped by pines will discourage other plant growth)
• a combination of two or more of these reasons                      

BENEFITS OF THIS COURSE

• Increase the number of coniferous species and cultivars you are familiar with.
• Develop a foundation of framework for understanding different groups of conifers. This will make it easier to learn, understand and retain information whenever you encounter new species or cultivars in the future.
• Discover how extensive the study of conifers can be - the more you learn, the more you will realize there is to learn.
• Improve your capacity to propagate and grow conifers in different places and different ways.
• Begin to establish a reputation as an expert with conifers.