I’m passionately fond of raspberries (Rubus idaeus), so it’s a good thing that they are a perfect forest garden crop. Their native habitat is the forest edge and even commercially bred forms do well there. They are also worth mentioning just to show that, alongside the weird and wonderful species I have been writing about, some perfectly respectable, traditional crops grow in forest gardens.
The season is about a month late this year, but my raspberry year usually begins in June with the smaller, wild-type rasps. It’s the most colourful time in the raspberry bowl as I have red ones, yellow ones and even a beautiful apricot-coloured strain that I guess is a cross between a red and a yellow. These are the nicest fruits of the year and they mostly go on porridge or straight in the mouth.
A few weeks later the maincrop varieties start producing: I have Glen Ample, which gives superb yields of big juicy fruits with not much loss of flavour compared to wild rasps. These are the ones that go for jam and into the freezer (a great way to eat raspberries is simply to take them out of the freezer, pour some cream over them and let it semi-freeze, then eat). Come September, the autumn-fruiting varieties are ready: I have Autumn Bliss and Allgold. They will last until the first frosts, which last year meant that I had raspberries from June to December.
The secret to raspberries is to keep them well picked. If they are left for long on the cane then the older ones rot and infect the new ones and the canes soon stop producing. When picking, I pick off any berries that are past it: nipping them off and letting them drop to the ground seems to be sufficient. I find raspberry-picking a very pleasant experience compared to the tedium of picking currants. It is almost entirely done by touch: a raspberry is ready when it feels soft and just slips off the receptacle (the fleshy bit in the middle) with a gentle pull. If you have to tug, you leave it; if it squidges, you drop it.
Martin Crawford suggests leaving raspberry canes unstaked and letting them wander where they will. I do some like this but I also find it useful to grow some in the traditional way. This involves growing them in lines with a wire frame that I tie the new canes into and cutting out the old season’s canes once they’ve finished fruiting. It takes a little work but it helps to keep diseases down and makes the fruits very accessible, which I think saves work overall. It also prevents the laden canes from bending to the ground and spoiling the fruit. The autumn varieties are treated differently: they are very vigorous varieties that are cut down completely at the end of the year and then fruit on the first-season canes.
Raspberries are the middle layer in the forest garden so they can have other crops both above and below them. Cultivated varieties don’t like much shade but they do benefit from growing surrounded by trees, presumably because of the shelter. By contrast, my wild type plants have wandered under the plum and still produce a good yield. All my rasps seem completely unbothered by having other crops growing at their base: in various parts of the garden they have their feet amongst wild strawberries, wild garlic, salsify, mallow, wood violet, Solomon’s seal, hedge garlic, cowslips and pignuts.