HortFACT - Autumn Raspberries - Establishment and Production
Autumn-fruiting, ever-bearing, fallbearing, or tip-fruiting varieties of raspberries have been known for many years. They flower and fruit on the tips of one year old primocanes late in the season. After bearing, the tip dies, so that only the lower part of the cane can bear fruit the following summer.
On the other hand, with main crop raspberries, primocanes are grown in the first season and kept over winter at which stage they are known as floricanes, to fruit the following season. After fruiting, these canes are pruned out, and the primocanes thinned and left to carry the following season's crop.
For autumn raspberries, after primocanes have finished fruiting, all canes are removed. The following season, new primocanes grow and bear fruit on the tips in autumn. The first crop can be harvested eight months after planting, so a return is achieved in the first growing season.
Autumn raspberries are grown for fresh use, rather than frozen use.
Soils and Water:
Raspberries will not tolerate wet feet. Well drained soil types are recommended for raspberry establishment and production. Wet spots may require drainage installation.
Irrigation will be necessary in dry years or localities, so a supply of clean high quality water is needed.
Shelter:
Shelter is beneficial. In exposed locations shelter is essential. Wind affects the plants indirectly, through reduced orchard temperature, increased evapotranspiration and reduced bee activity. Direct wind effects include damage to foliage and fruit, considerably reducing the proportion of crop suitable for fresh export.
Many autumn varieties are thorny. Because of the thorny nature of the plant and the ease of cane movement in wind, due to minimal crop support, wind damage can be quite severe without good shelter.
Shelter should be established before planting takes place. Aim to have sheltered blocks of about 0.4-1.0 ha.
Labour:
The site must be accessible to labour. Raspberry harvesting, grading, and packing are labour intensive activities.
Picking begins in mid-late summer, but exact timing is dependent on variety and district.
In Northern areas, picking begins in February and continues through late April or early May, on a daily, or alternate day basis, until cold temperatures reduce the crop and make harvesting uneconomic.
In Northern areas, Heritage and Southland reach peak yield in mid March and Autumn Bliss reaches peak yield in February/March.
Temperature:
Warm sites are preferable. Frosts damage flowers and fruit, and early autumn frosts will shorten the harvest. Avoid low-lying areas prone to frost.
Terrain:
Although machine harvesters are not yet well developed for autumn raspberries, flat land is preferable if machine harvesting is contemplated. Contour should not limit machinery operations such as spraying and mowing.
Three cultivars currently available are Heritage, Southland and Autumn Bliss. Estimated yields from Heritage and Southland for the first three seasons are shown in the table below.
Table 1: Estimated Yields from Heritage and Southland (t/ha)
| Year | 1 | 2 | 3 |
| Heritage | 2.25-2.75 | 5.0-6.25 | 6.25-7.5 |
| Southland | 0.75-1.25 | 3.75-5.0 | 5.0-6.0 |
There is evidence to suggest that yield drops rapidly in the fourth to fifth season. The drop may be a result of the necessary drastic pruning, in which all cane is removed each winter. An entirely new stand of canes must grow to carry a crop each year.
Still better cultivars are needed, with large firm berries, high yields, good flavour and storage life, and possibly suited to mechanical harvesting. New cultivars are under development and trial quantities are available. Both HPI and Joan Squire are available for testing.
Heritage:
Bred at Geneva, New York State, USA, 1969. Cane growth is prolific, vigorous, sturdy, and thorny, with canes often 1.5-2.0 m high.
Exceptionally firm fruit, average berry size is small to medium sized. Berry size decreases rapidly from large to small, after the early part of the season. Flavour is moderate. Berries are well presented on fruiting laterals and store well. Berry colour can change from bright red to dark purple/red after harvest.
Harvesting can extend from February through May, until frosts stop further development.
Southland:
Cane growth is vigorous, but the canes are less sturdy than those of Heritage. Mature canes are smooth and pinkish/purple.
Berries are medium sized, softer and juicier than Heritage, but store well. The berries prominent hairs and do not develop colour evenly. Berries retain bright red colour after harvest. Average berry size decreases through the season.
Southland presents a worthwhile double cropping opportunity. Primocanes are grown and cropped for autumn production, then pruned and trained as for summer cropping raspberry varieties. The floricanes produce a worthwhile summer crop in the next November/December, while new primocanes are growing to produce an autumn crop later that same season.
Southland fruit does not ripen until late February and cropping finishes before Heritage. Southland yield is less than Heritage, especially in the first season.
Autumn Bliss :
Bred at East Malling, U.K., 1974. Autumn Bliss produces an early autumn crop starting before and finishing after Southland. Canes are numerous, moderately strong, upright and spiny. Only minimal cane support is required.
Fruit is large, sometimes hard to remove by hand, medium red in colour and of mild flavour. Fruit is not as firm as Heritage or Southland.
Autumn Bliss is susceptible to Raspberry Bushy Dwarf Virus (RBDV) and in New Zealand, has shown considerable yellowing of foliage as a result of RBDV infection. This will often result in crumbly fruit, where small pieces of fruit detach from the remainder.
Varieties better suited to New Zealand conditions and market opportunities are required.
New Zealand New Variety Development
Autumn Bliss was used as a parent for crosses, to produce new autumn fruiting material, until RBDV susceptibillity was identified. Most of the resulting seedlings are showing RBDV susceptibility.
A Waiau X M.82 Glen Moy hybrid, presently labelled H.P.1, is showing some promise for autumn fruiting, commencing harvest three weeks before Heritage. Fruit is dark in colour, softer than Heritage but firmer than Autumn Bliss.
Other autumn raspberry breeding work continues, using material from the next generation of "Glen" material bred by Scottish Crops Research Institute.
Land preparation:
All perennial weeds must be eliminated before planting. This is vital for successful plant establishment. Strip cultivation, such as rotary hoeing, creates a suitably loose planting area.
Before planting, a soil test should be done. Fertiliser can then be applied as required and worked in before planting. Optimum soil readings (Soil Fertility Service soil test readings) are: pH 5.8-6.5; calcium 7-12; potassium 8-15; phosphorus15-30; magnesium 16-30.
Organic matter levels are important for healthy raspberry root system development. A soil organic matter level of 5% is recommended. Fertiliser requirements should be guided by plant performance, and crop nutrient removals. Fertiliser should be used to replace nutrients removed by crop, as indicated below
Table 2: Crop Nutrient Removals (kg nutrient removed/tonne fruit removed)
| Nutrient | Removal |
| Nitrogen (N) | 5 |
| Phosphorus (P) | 1 |
| Potassium (K) | 5 |
Plant material and planting:
Plants will establish from almost any plant material with roots, including root cuttings. ‘Mother’ plants, that is plants with multiple cane bases which have developed direct from the previous season's plant, result in more rapid establishment and higher yield in the first growing season than other types of plant material.
Autumn Bliss, Joan Squire and H.P.1 are available from the New Zealand Berryfruit Propagating Company, 2 Brook Street, Lower Hutt, Phone/Fax (04) 569 8263.
Heritage and Southland plants are normally removed as surplus plants from established raspberry gardens.
Figure 1: Plant types: (A) mother plant; (B) immature sucker; (C) mature sucker.
In the first growing season, the crop establishes evenly and rapidly if planted at close spacing, i.e. 30-50 cm between plants. Spacing is often determined by cost of planting material. Newly established plants will rapidly develop to fill the space between plants. Plant spacing has little effect on the second and subsequent season's growth.
Between-row spacing should suit the grower's tractor and machinery width. Spacings of 2.5-3.0 m spacings are often used.
Weed control:
It cannot be assumed that the same herbicides and application rates used on main crop raspberries can be used with equal safety on autumn raspberries. The crop is borne on the tips of 1-year-old canes, so a herbicide check to early primocane growth each season can result in delayed and reduced crop.
Early weed control is essential until plants are established and new primocanes are growing. Before new shoots grow in spring, Simazine can be used at a low rate. A number of other agrichemicals are registered for weed control on raspberries. Product selection and application should be guided by plant age, product label, soil type and any relevant local experience. Roundup is not an appropriate material to use, because of potential damage to buds and emerging shoots at the cane base.
Additional hand-hoeing can be expected, especially in the first growing season, until the new primocanes establish, to smother and shade out subsequent weed growth.
After removal of canes in winter, spot treatments can be applied for problem weeds. This results in a block with bare ground for a residual herbicide application in spring.
Cane management:
Points to watch in cane management are base width, tipping, support, and removal.
Too many canes in too wide a row results in overcrowding, increased difficulties in harvesting and pest and disease control, and no advantage in yield .
When canes are manually thinned in a row, new canes rapidly grow into the available space. To reduce the number of canes, cane base width is restricted. This is achieved chemically or manually. A cane base width of 30 cm, is about the maximum practicable width, with the optimum being considerably less for high yield and quality.
Mowing can contain the cane base width. Desiccant chemicals such as diquat or Buster applied along either side of the cane base also help to confine width, reduce the amount of weed growth from between rows into the rows, and may reduce the number of mowing passes needed per alleyway.
A row of lightweight posts, 0.6 m in the ground, with wire or string attached and running along either side at 1 metre above the ground, is sufficient to contain canes in the rows. Posts should be spaced at about 10 m intervals along the row, and placed in the centre of the row. End posts may be permanent and therefore need to be more substantial. A No. 1 fence post, 0.8 m in the ground, should be sufficient.
This support structure may not be adequate for ‘Southland’ which requires taller posts (1.8 m above ground level) at more frequent intervals.
In the second and subsequent growing seasons, another run of wire or string may need to be attached at the top level of the posts to support the taller canes.
Old canes should be removed from the block to improve crop hygiene.
Insect pests that can cause major problems include:
Control early in the season is particularly important, because once flowering begins, insecticide use is limited to less persistent and effective chemicals. With effective control of insect populations until flowering, insect problems over the harvest period are considerably reduced.
The major fungal disease is grey mould, Botrytis cinerea. Other diseases found on main crop raspberries can also be found on autumn raspberries.
Botrytis infects only through dead or dying tissue. Flowers opening in late December and continuing through the season leave many dead and decaying parts on the plant for infection to occur. Berries damaged by wind can also be infected.
The Botrytis fungus produces many spores, which are blown about in the air. Fungal growth is favoured by warm temperatures and high relative humidity.
Good spray coverage and timing is essential, to ensure effective control of pests and diseases before flowering starts. Spray schedules are available from New Zealand Berryfruit Growers Federation.
Over the lengthy harvesting season, only a small proportion of the crop is picked on any one day. Fruit is picked early in the morning, after dew has evaporated, but before hot daytime temperatures occur.
Berries are harvested by hand into small containers, carried on waist belts by pickers. The containers are regularly collected from the field and packed and cooled quickly.
Berry maturity at harvest influences post-harvest performance. Fruit should have good size, flavour, and good travelling quality.
Berries can be graded into three categories as they ripen:
Export fruit is harvested when it just reaches the firm red fruit stage, so that shelf life to reach distant market destinations is maximised. Fruit for local sales is harvested between firm red and soft red. Process grade fruit is harvested soft.
To keep pace with the rate of berry development, a crop normally needs picking on a daily or alternate-day basis, at the pink to firm red stage. Berries should not be harvested wet or damp, as this favours Botrytis infection and berry damage.
The picked fruit should be precooled on the property as soon as practicable, to reduce field heat once packed. Subsequent movement should be under refrigerated conditions so that a cool chain of distribution is achieved from the grower's property through to the consumer.
Rapid cooling after harvest, minimised temperature fluctuations, and cool chain distribution ensure high quality berries have sufficient life to arrive at markets in a desirable condition .