Having raspberries in your garden allows you to revel in their delicious fruits all summer long. Just remember that pruning raspberries is vital for ensuring bountiful future harvests. Read on to learn how to prune those berry bushes to keep them in great shape.
All About Pruning Raspberries
It’s only since working in gardens myself that I’ve become aware of just how many of us green-fingered folk have fruit gardens. In addition to a the obligatory well-sized veg patch, many of my customers had ample-sized fruit orchards. Others had abundant and overflowing fruit cages, unlimited pots of blueberries, and rows of messy, plump, and utterly sublime raspberries.
The peculiar part is that very few people actually know how and when to carry out the annual pruning chore. Today I aim to change that, and take you through my recommended method of pruning raspberries. I’ll do this step by step, in an easy-to-follow, straightforward way that someday, you may be able to share with someone else.
Most raspberry plants flower late in the spring, and bear their fruits in early to mid summer. These are known as summer-fruiting raspberries. Their fruit crop is produced on two-year-old canes.
Below are some of these summer-fruiting:
- Tulameen – This is quite a new, tall variety that grows to around 6 feet. It’s a heavy cropper (which stores well), with good disease resistance.
- Glen Ample – Another heavy cropper with an extra-long fruiting period and good disease resistance.
- Malling Admiral – Quite a tall variety, with large deep red fruits and good disease resistance. Give it a sheltered spot away from strong winds.
Not all raspberry cultivars are pruned in the same way, so it’s imperative to know whether you have summer- or autumn-fruiting canes.
Autumn-fruiting raspberries have a different growth cycle. These flower on the first year’s growth (the newest part of the plant), in late summertime and produce their fruit in the autumn.
Some of my favorite autumn-fruiting cultivars are listed below:
- All Gold – Produces a lovely yellow raspberry with a high yield.
- Autumn Bliss – This well-known cultivar is a firm favourite amongst the gardening community.
- Joan J – A good prickle-less cultivar, making handling for pruning and picking much more bearable.
- Polka – This is quite a tall cultivar at around 6 feet. A heavy cropper whose fruits store well.
We use a pruning cycle to encourage strong new growth, which replaces the old canes as they continue to fruit and die off. Once you’ve established whether you have summer or autumn raspberries, follow the pruning instructions below.
How to Prune Summer-Fruiting Raspberry Canes
Allow your canes to be approximately 4 inches apart per row.
For this “how-to” guide, I’m going to assume your plants are aged two years and older. You’ll find this guide particularly helpful when your raspberry canes have grown slightly out of control.
- In late winter, cut back all of the canes to 5 feet above ground. This will remove any weak and dead parts and encourage new lateral growth. This new growth will then produce fruit.
- The following summer, remove any emerging canes from the base of the plant, and any that are misplaced. Your remaining canes should be 4 inches apart per row, with fruit forming on the previous year’s growth. Should you have new canes in a good position, tie these in.
- Cut all of the fruited canes down to ground level in late autumn. At this point, there will be some new, young growth. Tie this in at 4-inch intervals to replace the old. When your plants have grown taller, loop the new top growth over and tie this in too.
How to Prune Autumn-Fruiting Raspberry Canes
These produce their crops on the lateral growth towards the ends of the current year’s canes. Fortunately, they have a no-fuss pruning regime.
- It’ll take a good year for your canes to become established. Deal with all first-year raspberry canes the same way regardless of type. All you need do is tie the canes in at 4-inch intervals along your row and allow them to grow.
- In the 2nd and all subsequent years, cut the canes down to ground level in early spring. This shall encourage new fruit-bearing canes to grow..
- In early winter—once your canes have finished fruiting—cut all canes back down to ground level.
And there we have it: a straightforward guide to pruning your raspberry row. This in turn, encourages productive growth and good fruit crops.
Top Tips for Keeping your Raspberry Canes Happy
Raspberry plants are the most shade tolerant of all cane fruits. They have a life cycle of well over 10 years in some areas, and are happy to grow on many soil types, apart from dry or shallow chalk.
- Plant this wonderful summery fruit in well-drained, slightly acidic soil. Choose a good light position away from strong winds, frost pockets, and overhanging trees.
- If you don’t have the ideal conditions mentioned above, you can still grow raspberries. Look into cultivars that flower later in the year and are more frost hardy. Make sure your site has a good amount of light and your ground is well dug prior to planting for greatest success.
- I always incorporate a good amount of well-rotted manure into my planting trench and keep my canes well tied in from the start. The added nutrients will keep my plants happy and produce strong growth.
- I also encourage annual springtime mulching around raspberry canes. This gives them a further nutrient boost for the oncoming fruiting season.
- Always use clean, sterile snips when pruning your canes. This cuts back on the possibility of damage or disease.
- Keep your fruit canes free of weeds, leaves and debris. This keeps the environment around your plants clean, and puts off any unwanted garden pests
- Finally, a seemingly obvious but important tip: please wear good gardening gloves when handling and pruning your raspberry plants. It only takes a second for thorns to get into your hands, but weeks to get them out. I offer this advice from experience!
Raspberry Cane Problems
In an ideal world we would have no problems, pests or diseases to interrupt the growth of these wonderfully sweet, versatile fruits.
Experience has taught me that being forewarned is forearmed. Therefore, I shall pass on some useful knowledge on what to look out for if your raspberry canes are under-performing or looking a little “under the weather”.
These quintessential summer fruit canes can suffer from a variety of problems. I’ve created a list below to help identify the cause.
- Pigeons – These tend to be the bane in of my life come summertime, and consume far more of my raspberries than should be allowed! To avoid them, cover your raspberry canes with a good, fine fruit netting. This should keep your fruits safe from greedy beaks.
- Raspberry Beetle – The pupae of these hairy little critters can live in the planting soil underneath the cane row. A raspberry beetle attack causes smal,l dry patches in the fruits, towards the stalk. There may even be tiny grubs inside the fruits.
These tend to create more havoc for the summer-fruiting cultivars. Control them organically by using a pheromone trap, or by using a deltamethrin-based spray. This spray will be sold at your local garden centre. A good way to ensure your soil stays clean is to hoe the planting area in springtime. This should bring the hidden pupae to the surface, to be eaten by birds.
- Raspberry Leaf Mites – These mites are microscopic, sap-sucking insects which cause yellowing patches on the upper side of the leaves in early Summer. Affected canes often develop odd-shaped leaves on any new growth and top leaves of your plants. This, although unsightly, does not tend to interfere too much with the plants fruiting potential. Alas, there is no chemical control available.
- Raspberry Cane Blight: This can be seen identified in the summertime by dead fruit leaves, followed by subsequent cane dieback of canes. You’ll also notice the bases are brittle and darker in color. The blight is actually a fungal disease that enters the plant through small wounds. It can be quite serious if widespread or left untreated.
For small infections, use a fruit and vegetable disease control spray on your plant. Should this infection be on a larger scale, however, remove and burn the infected canes and replace the planting soil.
- Raspberry Spur Blight – A fungal disease which can cause the canes to become less productive. The noticeable purple-coloured patches on the canes can be treated with a fruit and vegetable disease control spray. Prevention is the best cure in this instance, so be sure to keep planting areas clean from weeds and debris. In addition, avoid any overcrowding in your raspberry rows.
Diseases and Viruses:
- Raspberry Rust – You’ll identify this via small pustules on the plant leaves. As the infection takes hold, the rust patches change colour: from yellow to orange and finally to black.
To control this disease, remove and burn any infected leaves from your raspberry canes. Clean all fallen leaves away in late autumn. This should stop the infection carrying over to the following season. Use a fruit and vegetable disease spray to eliminate this infection.
- Raspberry Viral Infection – last but by no means least, lets talk about viruses. These are a real problem to fruit growers and can lead to an entire row of canes having to be dug up and destroyed. An infection of this sort can be spotted as a marbled yellowing of the leaves, stunted growth, under-productive crops, and weak fruit canes.The viruses are transferred from infected plants by sap-sucking insects like Aphids, nematodes, and the lethal leafhopper. Since there is no known cure, my best advice is: prevention. Always buy guaranteed healthy stock plants, and keep your planting area clean from weeds, which are a major source of infection.