How to Grow Raspberries
Select an everbearing variety, practice a few trellising and pruning tricks, and pick berries from July through fall
You may think the sheer pleasure of wolfing down ripe, juicy raspberries is reason enough to grow them. But raspberries are not just another tasty berry; they are loaded with healthful attributes. They’re high in fiber and contain vitamin A, folate, antioxidants, and numerous minerals. The juice contains vitamin C, and those sometimes-annoying little seeds contain vitamin E. And, of course, if you have a raspberry patch, you have endless dessert possibilities. The keys to raspberry success are careful selection of plant type, a solid trellising system, and husbandry techniques that match the needs of the plant. Once everything is in place, your raspberry patch will provide you with many years of satisfaction.
Get more berries with the right varieties
We chose to plant an ever-bearing variety called Summitt, after asking our local agriculture office which raspberries are recommended for our area. We also taste-tested berries from local berry farms (an important step) to determine our favorite. We then shopped around for rooted canes that were certified disease-free.
Various raspberry cultivars will flourish in USDA Hardiness Zones 3 to 10. A little homework will reveal the right raspberries for your location. Take your time selecting because raspberries come in varying shapes, sizes, and colors—red, purple, golden, and white.
So why did we choose an ever-bearing variety? We love raspberries. We’re willing to pick fruit every day until frost so that we can eat our fill, give some to the neighbors, freeze some for winter, and leave the rest for the birds. Summer-bearing raspberries fruit for about a month, then it’s all over (the fruit and the work) until next year. Everbearing raspberries, treated well, are just that everbearing. One mild winter, we found a few ripe berries still hanging on in December. Once established, everbearing raspberries—called fall-bearing by some—begin production in our area in July. The canes are usually so loaded down that they tend to bend over their support wires. Summer-bearing varieties generally fruit earlier, usually by a few weeks, so we also planted a few bushes of wine red ‘Brandywine’ to enjoy while we wait for the heavier-producing main crop. For variety, we added the yellow-tinged ‘Golden’, which is ever-bearing. Raspberries multiply precociously, prodigiously, and prolifically. If you plant one cane this year, you will have a dozen or more in the same spot next year. Raspberries are joyfully exuberant about procreating by underground runners, poking up impressive numbers of healthy new plants all around the original patch. I don’t consider this to be a problem, though, because one whack of the hoe takes care of them. You can also give them to a friend or use them to extend your patch.
Our two-row raspberry patch is 7 feet wide by 33 feet long. If I were to do it all over again, I would make it 9 or 10 feet wide to allow more elbow room for picking between the rows. We have 3 feet between rows, which is just barely enough. Four to 6 feet would be better.
Avoid pitfalls with raised beds and trellises
Raspberry plants hate wet feet, and they are heavy feeders. We addressed these two critical issues by building a 20-inch-high raised bed and filling it with a mixture of four-fifths good garden topsoil blended with about one-fifth of sand, peat, and manure. If like us, you have acidic soil, you will also need to add some lime because raspberries prefer a soil pH of around 6.0. We left one end of the box open to allow easy access for our wheelbarrows, then closed it in when the box was full. This job can be done in the fall so that you are ready to plant, come spring.
If you have rich, deep soil that drains well year-round, you can simply plant your raspberries in a permanent garden site. Not us. The Pacific Northwest gets rain all winter, and many gardeners lose raspberries to root rot because they make the mistake of planting their raspberries’ fussy little toes directly in the ground, which is often soggy clay-covered with a skim of topsoil. We also experience a two-month drought most summers. Raised beds allow us to have deep soil that holds moisture evenly yet drains well.
Don’t mix raspberries and nightshades
Be careful not to establish your raspberry patch in an area where you have recently grown tomatoes, peppers, or potatoes. This will help you avoid verticillium wilt, which these vegetables can carry and raspberries can catch.
How to trellis your raspberries
A raspberry plant laden with fruit is top-heavy and needs support to keep it from falling over. Because we wanted our raspberry patch to last a long time, we installed a support system.
- At the end of each row of raspberries, we buried a 6-foot-tall post 1 foot in the ground.
- Across the top and middle of each post, we fastened 30-inch-long crossbars with sturdy screws.
- We then stretched lengths of 16-gauge wire from the ends of each crossbar. In the beginning, we used only the top wire, but we found that some of the plants bearing fruit would fall over before they ever got to the top wire, so we added a second tier of wires about 2 feet off the ground.
- Sometimes the wires stretch from the weight of the plants and fruit, so we tighten them in early spring when we are pruning.
Be sure to prune raspberries in spring for a longer harvest
The main purpose of pruning is to get rid of older canes in favor of newer canes that will produce more fruit. In late summer, some of the newly planted canes will begin to fruit at the top of the cane and continue into fall. In early spring of the following year, while the plants are still dormant, it’s time to prune these now one-year-old canes, and here is where we do something special.
The common method of pruning everbearing raspberries is simply to cut all of the canes down to about 1 inch from the ground. Though it’s an easy way to go, this method eliminates the July crop; fruiting doesn’t begin until early fall, the reason some raspberry growers call everbearing raspberries “fall-bearing.” (This method is useful, however, if a disease has developed in your patch.)
We, instead, cut back the one-year-old canes the first spring to below the fruiting area, level with the top support wire. These shortened canes begin fruiting in July. In the meantime, leafy new canes, called primocanes, grow rapidly up from between the old canes. These new canes will flower and fruit later in the summer. We thin them out and clear away those suckers that popped up around the patch. The following spring, we remove the two-year-old canes completely to make room for new growth, cutting them off at the ground, and trim back the one-year-old canes. We usually top-dress our raspberry patch with manure and organic berry fertilizer in early spring. You can also prune summer-fruiting varieties using this method.
Common raspberry pests and diseases to watch out for
To keep your plants healthy and productive, make sure they don’t dry out in the summer. Remember: damp in summer, dry in winter. Spread straw or other mulch around the roots to help keep an adequate supply of moisture. If you don’t have a drip system, a soaker hose used for an hour or two each week should do the trick. In subsequent years, remember to top-dress the freshly pruned plants with several inches of manure or compost; fertilizer; and, if necessary, a sprinkling of lime. Raspberry plants need a significant amount of nitrogen to grow to their full height of 6 or 7 feet, but you should stop pushing high-nitrogen fertilizer on them as the fruiting time approaches. At this time, the plants must concentrate on producing fruit instead of leaves.
We have found our raspberries to be remarkably free of pests and diseases. Some of the critters that can attack raspberries are nematodes, root or bud weevils, aphids, fruit worms, and crown borers. This latter problem involves maggots girdling the emerging canes, which may then break off at the soil level or produce a poor crop. If you cut the canes to the ground, you can confound the borers and avoid drenching the root zone with an insecticide.
A few diseases you may encounter are fruit rot, root rot, and spur blight. Fruit rot is a fungus that sets up when canes are too crowded. The remedy is to prune for openness and to pick frequently in wet weather. Avoid overhead watering, and prune out fruiting canes after harvest. Root rot results in the sudden death of the plant right after flowering, when the weather turns warm. The only remedy is to plant resistant varieties in well-drained, rich soil. Spur blight shows up as dark, chocolate-colored blotches on canes in midsummer to fall when humidity is high. Infected areas on overwintered canes are silver-gray and produce millions of spores. A lime-sulfur solution is applied as a dormant spray, and good air circulation provides adequate prevention.
Planting Raspberries: Step by step
The best time to find plants—early spring—is also the best time to plant them, although you can put raspberries in anytime in the summer if you find some healthy plants. Spring plants, though, will establish better and may give you a few berries their first summer. I soak bare-root plants in a half-strength solution of vitamin B1 growth stimulant (½ teaspoon per quart water) for about six hours.
Don’t delay planting. The small plants will not stand for soaking longer than a day in the solution, and they will die quickly with dry roots. Should you receive dormant bare-root plants by mail before you are ready to plant, put them in the fridge to keep them dormant.
Dig a hole 1 foot deep and 1 foot wide per plant. In our case, we set the plants 3 feet apart in a row. Put a handful each of manure and organic fertilizer in the hole. Add some water, pop the plant in, then carefully tuck the soil around and over its roots. Make a small depression or basin at the surface, a place for rainfall to accumulate.
Cover the ground around the plants with mulch—no more than 3 inches deep. We laid landscape cloth over our path between the rows and covered it with wood chips. Drip irrigation is the ideal way to water raspberries, and this is the easiest time to install it.
1. To plant raspberries in early spring, first, check bare-root plants for signs of life. The sprout on this stem ensures it is viable.
2. Soak bare-root plants in half-strength vitamin B1 growth stimulant for about six hours.
3. Plant in a hole that is 1 foot deep and 1 foot wide with a handful of manure and organic fertilizer (recipe, below), and water well.
4. Surround your newly planted canes with a dense layer of mulch, no more than 3 inches thick, to help retain moisture.
Organic raspberry fertilizer recipe
I make a batch of this recipe each year in a big rubber trough. If you use this mix just before your raspberries blossom, reduce the amount of canola/fish meal by half (to 2 parts) because the plants need less nitrogen then.
4 parts canola seed meal or fish meal
1 part dolomitic lime (offsets the acidity of the seed meal)
1 part rock phosphate or ½ part bone meal
1 part kelp meal
Darlene White grows fruit, vegetables, herbs, and flowers in North Saanich, British Columbia.
Photos, except where noted: John Bray