A look at the findings of a new trial to find out which shredders perform best while breaking down prunings from trees and shrubs - plus, find out what else needs doing in the garden this week.

By Hannah Stephenson


Shredders have been around for a long time, breaking down prunings from trees and shrubs to enable you to reduce your tougher garden debris into a useful mulch quickly and effectively.

But the price and quality of shredders varies enormously and now Which? Gardening, the Consumers' Association magazine, has done some research to find out which shredders perform best and to let gardeners know what features to look out for when buying a shredder.

"A decent machine will cope with both woody branches and green twigs without jamming, shred a large amount quickly and relatively quietly, and produce fine shreddings ready to use as a mulch or to add to your compost. A bad shredder will be noisy, jam up easily and be tricky to unblock," the magazine reports.

Testers fed easy garden material such as straight, fresh branches through the 10 shredders on trial, weighed the resulting shreddings and rated how finely they had been chopped. They then shredded different materials including conifer prunings, spiny and woody branches and soft, fibrous plants and assessed how often shredders became blocked, as well as assessing the machines for ease of use, noise and ease of moving and storage.

Those voted the 'Best Buy' shredders included the Bosch AXT 22 D (£280), a quiet roller shredder which proved to be the best for all types of material, the Bosch AXT 23 TC (£400), a roller shredder which was best for more woody material, and the Al-Ko 2500R Power Slider (£229), an impact type which proved best for fine shredding.

There are two main types of shredders available - the impact shredder and the roller/turbine shredder.

Impact, or rapid, shredders chop up branches very finely with a spinning blade and are lighter and easier to move than roller shredders, but are also noisier.

The blades will go blunt over time, so make sure replacements are available when you buy an impact shredder. Most don't come with a collector so you'll have to improvise with a plastic sheet or tub.

Roller shredders are quieter machines which draw in garden debris, chopping it up and crushing it against a metal plate with a drum of blades. They are generally quieter and more compact, but they shred more coarsely.

When buying a roller shredder, make sure you can safely and easily access the blades to clear any blockages, as they tend to block more easily than impact machines. Also check that the shredder outlet isn't obstructed as some have a plastic grid over the outlet for safety, but this may lead to debris getting caught and blocking the machine.

To get the best out of your shredder, shred material shortly after pruning as the wood will be softer and easier to break down, and put the thicker end of branches through the machine first.

Prevent blades from clogging by alternating between sappy green waste and drier woody material, and always clean out the shredder after breaking down green waste or the blades will clog.

Try to keep the shreddings from different types of materials separate - woody shreddings are ideal as mulches, while green matter is better for the compost heap.

:: The full report is in the November issue of Which? Gardening. Sign up to Which? for a one-month trial for £1 and get access to all its product reviews, test scores and Best Buy or Don't Buy ratings. For more, information, visit www.which.co.uk/signup


Best of the bunch - Orchid

When everything's dull and damp in the garden, you can still enjoy a taste of the exotic with some orchids on your windowsill at this time of year.

Hybrid orchids are the most popular and widely available, from deep pinks to cool whites, which look wonderful in the conservatory or greenhouse, or on your windowsill.

They may look fragile, but they are generally easy to grow. Give them plenty of light (but avoid direct sunlight) and water them from beneath once a week, dunking them in a bowl of water for around 15 minutes before leaving them to drain for the same amount of time and then returning them to their pot.

Mist them every time you water and once they have finished blooming, cut the stems down to just above the second node and put them somewhere cool to rest and they should come back within a few months.

The easier varieties to grow include the delicately patterned odontoglossum types, which provide an exciting mix of colours and shapes.

If you want big, showy species, go for the cymbidiums, which are best in a sun lounge or conservatory. Cymbidium 'Tracey's Hill' produces deep yellow blooms in autumn, which can last up to eight weeks.

Cymbidium 'Red Baker' is another good choice, producing deep pink flower spikes in the autumn, which last well into winter. Among the UK's best-selling houseplants are the phalaenopsis types.


Good enough to eat... Winter cabbage

You can enjoy cabbages virtually all year round if you choose different varieties, but winter cabbage must be one of the best for filling in that gap of fresh greenery so often lacking at this time of year.

The ground should be dug in autumn, working in plenty of compost or well-rotted manure. Cabbages don't like acid soil, so add lime, if necessary in winter.

Cabbages should be grown in a sunny spot in firm soil. Sow thinly in shallow trenches and cover the seeds with soil. Thin the seedlings to around 8cm apart and they'll be ready for transplanting when they have five or six leaves. Water the rows before moving them to their final spot, leaving 30cm between plants for compact varieties and allowing 45cm either way for large-headed varieties.

Winter cabbages should be sown in May, transplanted in July and cut from November onwards. Good varieties include 'celtic', an F1 hybrid of a savoy and winter white cabbage, and 'Christmas Drumhead', a dwarf type which can be cut from late October.


Three ways to... Grow herbs in between paving

1. Clean out the crevices, removing loose cement or soils. Sprinkle potting compost over the area and brush it into the cracks before sowing seeds of herbs such as oregano.

2. Add sharp sand or fine grit into the bottom of the planting hole for herbs which like good drainage, such as chamomile.

3. If people are likely to be walking over the area of paving you are planting up, go for herbs which can stand a lot of wear and tear, such as thick, mat-forming thymes, many of which release a fragrance when crushed.


What to do this week

:: Protect members of the cabbage family with netting to deter hungry birds.

:: Cover alpines which don't like wet weather.

:: Don't walk on the lawn after persistent rain.

:: Continue winter digging and manuring.

:: Plant new tubers of Jerusalem artichokes.

:: Put potted strawberry plants on their sides to prevent waterlogging.

:: Plant new rhubarb crowns.

:: Continue to be vigilant against slugs and snails by doing a daily patrol to remove any, particularly after rain.

:: Make sure stakes and ties on trees are secure.

:: If frost is forecast, protect tender plants with cloches or horticultural fleece.

:: Check your stored fruit and vegetables and remove any that are rotting.

:: Clean and repair tools before putting them away for the winter.