Brambleberries

How well established is this crop?

This crop has been grown commercially in the region for at least 10 years. Commercial returns, current growers and some level of regional based research is available to help those new to this industry.

Background

Because the growth patterns and requirements of the following berries are similar, it is easy to put them together under the title 'Brambleberries'. The groups actually contains
- Blackberries
- Boysenberries/Youngberries
- Other new hybrid berries

Brambleberries have always been popular in New Zealand and are even more so now that we recognise the added health benefits of consuming fruits such as this. The fruit can be sold fresh or frozen, on both the domestic and export markets.

Winter Chilling and Frosts

A number of different brambleberries are being grown successfully at the Crop Centre in Cromwell. This tends to suggest that they are tolerant of frosts in the winter months. However, frosts from October onwards can cause problems as the plants are flowering. Some form of frost control using either overhead watering or wind machines should be considered if growing these crops.

Rainfall and Irrigation

Brambleberries are not directly affected by rain but it can cause increased disease pressure near to harvest.

Brambleberries do not like drying out, so irrigation is essential especially in inland areas of Otago. This is especially important as the berries near harvest. They swell dramatically in size in the last few weeks. Dry soil in this period will lead to undersize and poor quality fruit.

Using mulch will reduce the water loss from the soil and mean less irrigation is needed. Drip methods are the best, rather than overhead systems as they deliver water directly to the plants root zone, reducing leaf wetness and associated disease problems.

After harvest, many growers reduce irrigation water. This slows plant growth down and prevents them shooting away with new vegetative growth. Soft growth such as this, is very vulnerable to winter frosts and can result in plant death.

Wind

Like most high value crops, shelter from the wind is essential. This can take the form of natural tree shelter or artificial shelter using wind cloth. A good rule of thumb when designing shelter is to multiply the final height of the shelter by 5. Use that measurement as the distance you position your shelters apart. For example, when using 2m high windbreak cloth, you will need shelters every 10m.

If using natural tree shelter, make sure the shelters running east-west are deciduous. This will allow sunlight into the blocks in the winter. Position all shelters at right angles to the prevailing winds. Talk to your local nurserymen when deciding on the right tree type for your property. They may also be able to help with design.

Soil

Different brambleberries have different soil requirements.

- Blackberries and boysenberries tend to be more tolerant of a heavy soil but will do best if it is deep and free draining.

- The hybrid berries (tayberries, marionberries, dewberries etc) have various preferences. Talk to your nursery, other growers or do some trial planting on your property, before commercial blocks are looked at.

Fertility

The different varieties of brambleberries all have different nutrient requirements. In general, they all need reasonable levels of soil fertility with a pH between 6-6.5.

Weed Control

Because brambleberries are a permanant crop, perennial weeds are a major problem. The best time to lcontrol them is beore planting. As the bushes grow over the years they will return into the blocks. Hand weeding with hoes is a good way to control these weeds but it is very time consuming. Using agrichemicals is faster but can be a risk because of the close proximity of the feeder roots to the soil surface.

Varieties

A range of varieties are available to the new grower. Contacting an established producer may take some of the guesswork out of selecting varieties suitable for Otago conditions. Other options include approaching some of the brambleberry breeders within HortResearch. See contacts section at the end of this datasheet. Some varieties may ripen too late for some areas.

Pests and Diseases

Brambleberries are relatively free of pests and diseases. Leafrollers, scale, leafhoppers, mites and grass-grub do affect the bushes but are easily controlled with insecticides.

The main fungal diseases include powdery mildew, downy mildew and botrytis. These reduce if the plants are grown in the correct environmental conditions. Agrichemical sprays can also be used.

Birds are a major problem as the berries start to change colour and ripen. They are best controlled by netting the blocks, shooting, or using other means of bird scaring.

Layout

Most brambleberries are planted in rows 3m apart to allow for tractor access. The distance of plants within the rows depends on cultivar but usually ranges from 1-2m.

General Management

Brambleberries have a three year rotation of canes. In Year 1 they grow the cane. This fruits in Year 2 and by Year 3 it begins to die off. Most growers prune out these canes in the winter following Year 2. This keeps the bush turning over new wood and keeps production up. New canes are known as primocanes and the fruiting canes are known as floricanes.

The key tasks during the season are attending to irrigation needs, fungicide and insecticide spraying. Harvest period is exceptionally busy so it is best to grow a number of different varieties to try and spread this period out. As the plants become dormant autumn weed control is needed and then obviously pruning. Removing the pruned canes from the block and burning them, reduces the chances of carrying over disease from one season to the next, however mulching is a more sustainable practice.

Harvest

Blocks need to be picked over by hand every 3-4 days or more frequently if the temperature during this period is high. Picking directly into the punnets that the berries are sold in, reduces handling and makes for a better quality product. Removing them from the field immediately and getting the fruit into a chiller also is advisable.

Equipment

Small blocks can be managed with a back-pack spray unit and general gardening equipment. Larger blocks are best managed with a small tractor unit for spraying and grass mowing etc.

Returns

Returns depend on the final use of the fruit, the timing of harvest and the value of the $NZ. The figures below are indications only.

Frozen blocks of fruit for processing reach $1.80 - $3.00/kg. Individual Quick Frozen (IQF) berries reach $3.00-$4.50/kg while fresh fruit can achieve upward of $4.00/kg.

Contacts

If you are thinking of growing strawberries, talk to some local growers or contact the following organisations.

For soil fertility information
http://www.hortnet.co.nz/publications/guides/fertmanual/boysen.htm
www.hill-laboratories.com

For plants
Strawberry and NZ Berryfruit Propagators Ltd
11 Grenville Street
Lower Hutt
Ph 04 569 8263
e-mail propco@xtra.co.nz