Raspberries - Method
Choice of site and preparation
Rapsberries will do best on soil with excellent drainage. If this is not the case, plant on raised rows 35 cm above the middle of the aisles. For the other aspects of choice and preparation of site, follow the recommendations given for strawberries above.
Since raspberries can also be planted in fall, plowing, tilling and soil amendments must be done in mid-summer. Raised beds must also be made at that time. A cover crop can be established for the aisles in mid-August since germination and growth are best at that period.
For spring planting, apply basic fertilizers, till and plant early for best results. Space plants according to varieties, cultural practices and machinery used. Normally, plants are set 40-60 cm apart in rows spaced 3 m. The higher density in the row achieved by closer spacing at planting will eventually make weed control easier. Use certified plants from a recognized certification programme. Consult our variety list for a detailed description.
Keep plants refrigerated until planting. Plant so that the roots are covered with at least 5 cm of soil. Plant deeper in fall to minimize heaving. Add water and a starter fertilizer at planting and keep a sufficient soil moisture level thereafter for good establishment.
After planting cut back cane stubs to ground level so that fruiting will not take place at the expense of new shoot growth. This practice may not be as effective if plants are not dormant at planting.
Frequent shallow tilling aerate the soil and destroy weeds. Later, the use of a contact herbicide will help complete weed control for the season. Near perfect weed control in the two first years after planting will insure the longevity of the planting.
Mow the aisles frequently so that the plants used as a cover crop are kept out of the row. If clean cultivation is used, shallow till early in the season then sow a spring cereal in mid-August
Band a high nitrogen fertilizer twice during the growing season.
If plants have not developed well enough in the first season, mow canes back to ground level in early spring. This will increase cane density and reduce the invasion of gaps in the rows by weeds. A much better yield in the third season will more than compensate for the small crop loss in the second season.
In early spring, apply a residual herbicide and band a complete fertilizer according to soil or leaf analysis. Insure that the plants receive 3-5 cm of water per week during the period of fruit development. Apply less water but more often in lighter soils.
Pruning is often neglected with negative effects on yield. Pruning must start with the narrowing of rows first when new shoots are 15-20 cm in height and a second time before harvest. The extent of this pruning is determined by the ideal number of canes which should be left for optimum yield. Since the optimum density is 10 canes per metre, narrow rows accordingly. If rows are narrowed as indicated above, pruning after harvest will be easier. The better light penetration and air movement of an opened narrow row will provide for large, healthy and more productive canes.
Trellissing of canes is another mean of obtaining good yields. Productive canes overloaded with fruit can be kept upright with a single set of wires on each side of the row. Different trellissing systems exist depending on grower needs.
Consult the Raspberries - comparative table for a detailed description of varieties.