Nothing compares with the sun-warmed sweetness of a raspberry freshly plucked and popped into your mouth. Mine aren't ready yet, but they will be soon!
Raspberries do not ship well, so the specimens we find at the grocery store, like most tomatoes, are simply not up to par with fresh from the garden varieties. The nice thing about raspberries is that that can grow in some unusual places. When I first moved into our San Jose home, I wasn’t sure where I wanted my container raspberries to end up, so I heeled them in (laid them down on the ground and covered the roots with some soil) in the unlikeliest of places - a 6 inch strip of soil next to a concrete slab, where the property line fence was installed. And then I forgot all about them.
Six months or so later, after unpacking, settling in, and beginning to work the garden and landscape, I came around the corner of my house and BAM! There, in the shade of my garage, the neglected raspberries had thrived and were climbing the fence! All in a 6 inch strip of what was probably construction soil.
What made that dubious location work was afternoon shade and a ready supply of water. It was winter in the Bay area and a rain gutter downspout pointed directly their way. You may not want to try growing your berries in such a questionable location, but it sure shows how tenacious these cane fruits can be. Once the plants are established, they can produce fruit for decades. In addition of the traditional red raspberry, you can also find cultivars that are golden, purple, and black.
How to grow raspberries
Raspberries love water. Sunburn is a common sign that your raspberries are not getting enough water. Our raspberries get nearly daily waterings from the bucket of water we collect in the shower as we wait for the water to heat up, at least when it’s not raining. At the same time, our heavy clay soil can also lead to drowning if there is too much water. Since raspberries have relatively shallow roots, regular light watering is better than less frequent deep watering.
Raspberries prefer cooler, damp weather, but you can recreate those conditions by adding them to a shade garden or growing them in containers under a pergola or on a shady balcony. The plants need lots of sun but they prefer a little shade in the heat of the afternoon. Raspberries grow best in soil with a pH of 5.5 to 7.0. They love raised beds and fence lines provide the perfect medium for trellising. If the cane tips reach the ground, rather than producing fruit, new roots will form, so trellising is a good idea. That’s how bramble fruits spread in the wild. They also spread using underground stems called stolons.
While you can start raspberries from seed, it is much more satisfying to start with cuttings, dormant bare-root plants, or potted seedlings. Ideally, you will remove any damaged roots or stems before planting your raspberries in a shallow hole, making sure that the crown is slightly above soil level. Spreading the root mass out, covering with soil, and patting it down to eliminate air pockets will help your plants get a good start in their new location. Be sure to water well, to help the soil settle. Plants should be placed 2 to 3 feet apart and new plants should be trimmed down to be only 6 inches tall, to encourage strong root growth. Black and purple raspberries should be spaced 3 to 4 feet apart.
Raspberry plants have perennial roots and crowns that grow new canes each year. These new green canes are called primocanes. Then they turn brown and go dormant over the winter, to one degree or another. In spring, these now 2-year old canes are called floricanes. Flowers and fruit are only produced on floricanes, so you don’t want to prune them out.
Fruit production varies between everbearing and summer-bearing varieties. Summer-bearing raspberries bear one crop in summer on two-year old canes, while everbearing cultivars have two crops, one small crop in summer on new canes and one heavier crop in fall on two-year old canes. Everbearing cultivars are sometimes called fall-bearing. It is a good idea to check with your local Cooperative Extension Office to find the best cultivar for your location.
How to prune raspberries
Raspberry pruning methods will vary, depending on the cultivar. Fruit-producing canes of summer-bearing red and yellow raspberries should be cut to ground level after harvest and removed. Thin primocanes to no more than 4 or 5 per foot. Fall-bearing raspberries can be treated the same as everbearing varieties, if you want both the summer and fall crops. Otherwise, leave the canes in place for an extra year. If you are growing black or purple raspberries, you will need to pinch the canes when they reach 2 to 2-1/2 feet in height and then again two or three times during the summer. This will promote lateral cane growth for more fruit. Be sure to remove any dead or damaged canes whenever you are working your bramble fruits. Canes left to grow a third year may produce some fruit on the lower part of the canes but they should be pruned out after that to make room for new canes and to reduce the spread of disease.
Raspberries pests & diseases
Raspberry pests include borers, spider mites, aphids, and Fuller Rose Beetles. Fungal diseases and raspberry leaf curl can also be a problem. Healthy plants are far less likely to be vulnerable, so you will want to feed your raspberry plants each time they start a new bloom cycle. According to UC Davis, 3 to 6 pounds of blood meal, feather meal, or fish meal should be applied for every 100 feet of row. Most of us don’t have a 100 feet row of raspberry plants, so I did the math and it works out to approximately 1 to 2 ounces per plant.
Raspberries are self-fertile, which means you can get fruit from a single plant. If you really love raspberries, and have the room, you can grow a raspberry hedge as part of your edible landscape!
Note: If you have never grown raspberries before, you may be surprised to learn that they ripen unevenly. One part of a berry will look ripe days before the rest of it does. This is okay, simply wait (if you can!) for the entire berry to ripen before picking.
I hope this information inspires you to grow more of your own food. You can ask your garden questions on my Home page.