Quality Planting Material

 Profitable plant performance is a combination of the plant's genetics and production environment, starting with the plant stock used for propagation, through the nursery system and into the plantation.

Quality Categories:

Growth:

Rate: fast enough to be profitable.

Habit: bushy, upright.

Branching: shoot numbers, angle, and internode length.

Foliage: sufficiently dense, colour, shape.

Flowering:

Time from plantout to first harvest: soon as possible

Flowering time: early, middle or late for the crop; fit to market requirements.

Harvest period: crops vary from a few days to a few months; 2-4 weeks would be average for a specific location; can be too short or too long.

Flower size, number, density, colour, and shape: consumer appeal

Stem yield: grower appeal

Postharvest characteristics:

Durability in shipping & consumer vase life: critical to viability as a product.

Plant Types:

Cultivars

Most have been selected, from native populations or seedlings in cultivation, for required characteristics from the above. Some have been bred with selected parents.

Propagated vegetatively, usually by cuttings. Plants are genetically identical. Degree of uniformity in size depends on propagation practices.

More expensive to produce, requiring a better facility, more skill and sufficient quantity of stock.

More predictable performance in field & market

Many new varieties are protected by Plant Breeders Rights, prohibiting unauthorised propagation.

Established plants

Provide cost effective plantation establishment for most growers.

Optimum size to plantout may be crop-specific.

Riceflower & Flannel must be planted quite small, without extensive root development in the container; Riceflower will be around 7-12cm high and Flannel Flower only 4-8cm at this stage; they will progress much faster and be more durable than larger plants, although establishing plants this small requires careful attention to soil tilth, irrigation and weed control.

Christmas Bush and the Proteaceae family show better field establishment success with slightly larger plants with a bigger root system in a bigger container.

Seedlings

Usually show high variability in the above quality categories, both between individuals and populations.

The export crops currently produced mainly from seedlings are in relatively early stages of development in cultivation. They include:

Christmas Bells: seedlings have been the most practical propagation method so far, being cheap & simple, though slow; potential divisions are limited by low shoot numbers and recovery time; tissue culture has so far been slow and costly. However flower form, colour, number and yield vary considerably.

Flannel Flowers: seedlings have often shown better vigour than cuttings, which establish more slowly and branch less; varietal selections are not yet widely available. Flannels seem to grow reasonably true to type from selected plantation seed.

Waratah production is already substantially moving to clonal (cultivar) plantations. The Protea industry made this move about 10 years ago, as witnessed by the consistently high export returns for King Protea, with consistent flower appearance and quality. Waratah has yet to achieve these levels, due to product variability inherent in seedling flower production.

All export products which have reached the mature development stage (high volume, 10 years + exports) are clonal products, eg Wax, Paws, Leucadendron.

Seedlings can be very useful as a source of new varieties, however many seedlings will be inferior; not recommended for commercial plantation production when good cultivars are available.

Some seedling crops may be able to be field grafted with proven varieties. This will still result in non-clonal rootstock.

Tissue culture

A valuable research tool, with continuing work in many crops.

Woody Australian plants have been generally difficult to develop to commercial viability, and there is no significant production.

Kangaroo Paw is exclusively produced by tissue culture because the plants outperform those produced by division or seed.

Grafted

Grafted plants aim to combine better root systems with the best varieties. They may offer better climatic adaptation, vigour, disease resistance and yield.

Difficult to produce, commercial production is limited.

Successful examples include Eremophila nivea grafted onto Myoporum, enabling a purple flowered, silver foliage desert plant to be grown on the East coast.

Quality Standards

Vigour

Plants should be actively growing when planted out. Good plants will be multi-branched, upright, well covered in green healthy foliage and new or recent shoots, which may be pinched out.

Professionally produced young plants are fully sun and weather hardened; plants grown in full sun conditions from soon after potting will have the necessary size, sturdiness and upright branching to achieve best early stem yields. Well-nourished plants are high in carbohydrates, which give high survival through the stress of transport and plantout.

Plants are grown in soil-less media, often pine bark based, for aeration with sufficient water capacity and disease suppression. The mix contains controlled release fertiliser, including a high iron trace element mix, suppling nutrients slowly and consistently over 6-9 months.

Roots

Plants should have visible fine new roots, usually white. The amount of root coverage of the outside of the potting mix should be enough to hold the mix together. Some crops need more root coverage. During winter most active growth may be in the roots.

Roots that are very thick around the bottom of the pot may benefit from 3-4 vertical cuts. Roots that are going around in circles are not likely to make good plants and should not be used.

Shoots

Young plants need to have a branch framework established quite low, as this will increase early yield. This framework is primarily achieved by use of the correct type of cutting material. These cuttings are already branched, have high bud numbers and are taken from strong mature trees; thinner, lighter cuttings are not used. A Christmas Bush planted with 2-4 main branches may produce several saleable 40-50cm stems in 12 months.

Readiness

Order

Specialist cutflower propagation nurseries usually grow to order so plants are ready to ship and plant out at the required time, when all preparations are complete and conditions are suitable.

Young plant production, especially in the less developed crops, is not always a completely predictable process; eg. Flannel seed germination can be quite erratic; cutting stock may not always be available in the required condition.

Order well in advance so you will be most likely to get your plants when you need them.

Plantout

Best times will depend on what and where. Crop specific recommendations should be sought from growers, plant suppliers and marketers. Ideally planting will be timed to reach useable production as early as possible, eg. a Riceflower crop may need to planted by March to have 18 months to reach a profitable size before harvest in September of the following year; planting 2-3 months later will result in a smaller harvest.

Best times for this region will generally be March - May and August - November, preferably avoiding the hottest and coldest months. Frost hardy plants, eg. Riceflower and Waratah can be planted right through winter; Proteaceae particularly dislike heat at plantout. Frost sensitive plants, eg. Christmas Bush should be planted after frosts (if any) in spring, but young plants planted in early autumn can be successfully protected against frost with application of anti-transpirant Envy®. Many plants make active root growth more in cooler weather, making autumn the preferred time for planting, allowing plants to make good root growth before shoot growth in the heat of summer.

However planting time may also be affected by availability of plants.

Timing

You must be ready to plant when your plants arrive, generally within a week and as soon as possible. Plants produced by specialist cutflower plant nurseries are not designed, in terms of container and mix, to sit around for extended periods, unlike plants intended for retail nursery sales. Plants should be at the best stage to plant when you get them; maintaining small container plants is a specialised operation and is not the grower's job; plants not ready should not be shipped. Likewise plants that are over-mature.

Arrival

Plants should be watered on arrival; take time to water thoroughly, as the small containers don't hold much water in the space on top of the soil. You may need to water a few times over an hour. If in doubt, take a plant or two out of the pot and look at the potting mix. Keep plants in sun, with some wind shelter.

Problems:

All nurseries have pests & disease problems at times; the critical factor is that only quality plants are shipped and planted out. Choose a supplier carefully.

Good nurseries back up their plants and guarantee their quality, within reasonable limits.

You must immediately advise the supplier of any problems on arrival.

Quarantine

Any plants that come onto your farm are potential sources of pests & diseases. The basic protection is to buy clean plants from a quality supplier. Secondary protection is achieved by keeping these new plants separate from any existing plantings or other young plants. Separate for at least 3-4 days. The worst soil diseases are carried in water so young plant standing areas must be completely drained, or plants kept on benches.

Irrigation

Should be installed and tested before the plants go in. Drip lines should be run for some hours to thoroughly wet the soil, plants can then be put in the wet spots using the drippers for spacing.

Plantout

Have plants completely wet before planting; by full immersion until air bubbles stop, if necessary. This helps the pots to come off smoothly; if they don't, hold upside down and gently tap one side of the pot's top rim on a hard object. Plant the root ball whole with minimum disturbance, unless the roots need vertical cuts. It is usually safer to add a small measured quantity of appropriate fertiliser around the plant on top of the soil, but under mulch, rather than under the plant. It may be better to wait a week or two before fertilising; the plants will still have adequate nutrition from the mix.

Maintenance

Check soil moisture frequently, especially in warm weather. Aim for a consistent moisture level. Bush may benefit greatly from poly tree guards, providing wind shelter, increased humidity and protection from small animals. Be very careful with herbicide near small plants. Mulch can be useful to moderate soil temperature and control weeds. Mulch should not be too dense, like soft grass clippings, but aerated, like woodchip or fibrous hay. Mulch should not touch the plant.

Do your own propagation?

You will need to set up a mini nursery facility. Its complexity will depend on what, where and how many plants you want to grow. Shelter & irrigation are needed, as is understanding of propagation and growing media and making cuttings. This is not rocket science but does require time & resources. Many excellent references are available on technical aspects of propagation, though most information is on traditional exotic crops.

Many growers choose to buy from a specialist and concentrate on their field planting.

If you do propagate, keep your operations clean, keep records and label your work.

Seed

Seed has the lowest initial cost, but may require considerable investment in time, skills & resources to establish. Suitable only for particular crops and objectives. Culling of the smallest 10-20% of seedlings is often good practice.

Cuttings

Early prunings are only of limited use as stock. The best cuttings may be on stems that could otherwise be sold in flower.

Grower Selections

There is great potential in every crop for new varieties with better overall performance. This may be market performance, as with a new flower colour or shape, or field performance, as with a better growth habit or yield.

Desirable new varieties can occur in self sown or cultivated seedlings, plants growing in the bush and sometimes by mutation, perhaps on one branch.

Natural distribution

Plants with a widespread range, like Riceflower, show great variation in many important characteristics, both visible, like flower form and colour, and less visible, like nematode resistance, susceptibility to leaf blackening and shipping durability. These variations also occur between individuals in the same population.

Riceflower

Riceflower varieties seem to have limited climatic suitability, particularly narrow leaf pink types in the warmer coastal zone. Local selections may offer much better performance if their flower quality is comparable.

Trials

New selections must be fully trialed against existing varieties before large numbers are planted. This trial process must not only confirm the field performance of the selection, but also clearly show acceptably high postharvest life and good shipping durability, as well as market interest.

Christmas Bush and Flannel Flower have extensive natural distribution, presenting good opportunities for varietal selection.

Many of the Eastern Australian cutflower crops discussed at this conference may be subject to State and Commonwealth laws regarding their propagation, harvest, sale and export. Check your state National Parks Service.

Paul Dalley © 1998

From Commercial Realities of Cutflower Production Conference, Grafton, May 1998, NSW Agriculture.

Mountain Nursery  www.mountain-nursery.com.au        email : paul@mountain-nursery.com.au  

phone/fax 02 6562 7450     mobile 0432 590 496
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Eastern Australian Cutflower Crops : development, propagation, cultivation & information services.