Raspberries grow on canes, not a woody shrub, and unsupported canes flop over under the weight of their own fruit. The fix is a simple two-wire trellis run along the row, with canes tied in as they grow, so fruit hangs clear of the ground instead of rotting where it touches soil or turning into an awkward tangle to pick through. Give plants full sun and space canes 60cm apart; a mature planting reaches around 1.8m, which is roughly the height the top wire should sit at.
Raspberries go in as bare-root canes over winter. In Northland, Auckland, Bay of Plenty, Gisborne, Hawke's Bay, Waikato, Taranaki, Manawatū-Whanganui, Wellington, Nelson and Tasman, plant anywhere from June through August. Further south, in Canterbury, Marlborough, the West Coast, Otago and Southland, the window is tighter and it's worth aiming for July specifically. Put the trellis wires up before or at planting, not after the canes are already established, since threading support through a row of grown canes is far more awkward than tying young ones in as they go. This is a moderate-water crop once settled in, so it doesn't need the constant attention a thirstier plant would, but don't let it dry out in its first season while roots are still establishing.
Raspberries spread by suckering from the roots, and left alone they'll colonise well beyond the original row. Plant them somewhere new suckers can be mowed off or dug out without a second thought, or bury edging around the bed deep enough to stop roots running under it. A dedicated raspberry bed, rather than a spot tucked into a mixed border, makes this far easier to stay on top of.
Which pruning method to use depends entirely on which type of raspberry is planted, and getting this wrong removes the exact wood that would have fruited. Summer-fruiting varieties carry fruit on canes that grew the previous year; once that cane has finished fruiting, it's cut out at ground level, since it won't fruit a second time, while the new canes that grew alongside it this season are tied to the wires to overwinter and fruit next summer. Autumn-fruiting varieties instead fruit on the current season's new growth, so the whole planting is cut back hard to ground level in winter and regrows from scratch to fruit again the following autumn. Check which type is planted before pruning anything, because the two methods are opposites and applying the wrong one to a summer-fruiting variety means cutting away the very canes that were about to fruit.
Which pruning method to use depends entirely on which type of raspberry is planted, and getting this wrong removes the exact wood that would have fruited.
Birds are the biggest threat to a ripening crop, same as most soft cane fruit, and will strip a row bare well before the gardener gets a picking; net it as soon as fruit starts to colour. Aphids are the other pest worth watching for. Cane blight shows up as canes that suddenly wilt, turn brittle and die back, usually entering through a wound or pruning cut, and affected canes should come out at ground level rather than being left to spread the infection. Root rot is the other real risk, and it takes hold in poorly drained soil rather than from underwatering, so a raised bed or well-drained site matters more here than extra irrigation.
It's rated an intermediate crop, and the trellis and pruning timing are most of the reason why; get those two things right early and the rest is straightforward maintenance. A newly planted row takes one to two years to reach a proper harvest, and an established planting then produces around 1-2kg of fruit per plant each season, ready to keep cropping for years off the same root system as long as suckers are kept in bounds and old wood is cleared out on schedule.