Thompson & Morgan Facebook Q&A Session 16th November 2012 - Your horticultural questions answered.

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Name: Shaun Osborne

Question: Hi there could you advise me on the how to cut back my red and black currant bushes?

Answer: Hi Shaun. Blackcurrants and Redcurrants need slightly different treatment but they can both be pruned from autumn to winter whilst dormant.

Blackcurrants fruit best on younger wood that was produced in the previous growing season so you need to aim to remove the oldest, less productive stems. These tend to be very dark in colour, making them easier to identify.

In the first few years after planting, simply prune out any thin or weak shoots, to leave a basic structure of 6 to 10 main stems. But in the following years you will also need to prune away about 20% of the main stems - cut them back to ground level or a healthy bud near the base of the plant. Always remove the oldest, weakest stems first, and any that are damaged or poorly positioned. This aim is to create an open bush, and encourage fresh new shoots to develop from the base of the plant. These will replace the ones that you have removed.

Redcurrants are slightly different - they form fruit on 2 year old wood. In the first 2 years after planting, the leading shoots need only be pruned by half to encourage branching and to create an open framework of about 8 to 10 main stems. Cut back any weak side shoots to one bud from the main stem to help encourage stronger new growth.

Once the main framework is established, you can simply prune back all new growth each year to just one bud from the previous year’s growth to create fruiting spurs. You should also remove any weak, damaged or poorly placed stems.

I know this sounds a little complicated but it’s worth getting it right in order to maximise your crops. Best of luck Shaun.

Name: Plum Ovelgonne

Question: Hello, I'm interested in your wild orchid collection offer but please can you tell me if rabbits and deer eat wild orchids? I have a woodland garden and I'd like to plant orchids but at the moment we also share the garden with rabbits. Also, will orchids have trouble competing with blue bells or should I plant them in a more open area?

Answer: Hello Plum. Like all plants, these hardy orchids are capable of holding their own once they are well established, but they will struggle to out-compete other plants while still young. However, this is easily overcome by clearing a patch of bluebells in the area surrounding them for the first few years, to give them the opportunity to establish properly. Unfortunately both deer and rabbits are quite partial to orchids and will happily munch their way through them. I’m afraid there are very few plants that deer and rabbits won’t eat if they are hungry enough! You could always try netting the orchids to protect them but this would rather ruin the effect. If your furry visitors are a such a problem then it might be better to stick to resilient, more common plants such as primroses, aquilegias and foxgloves which don’t cost so much to replace.

Name: Gaz RocknRolla

Question: I've got no main power connected to my greenhouse. So what can I use instead without burning it down, please?

Answer: Hi Gaz. There are two solutions to this problem but only one that I would recommend. You could run an extension lead with a circuit breaker from the greenhouse to your nearest source of mains power, but this is only ever a temporary solution and certainly not the safest. I wouldn’t advise this.

The best way to heat your greenhouse is to invest in a paraffin heater. They aren’t particularly expensive, fuel is relatively cheap, they are easy to operate, and perfectly safe provided that you follow the instructions - far better than the extension lead option. The main drawback is that they are manually controlled so they will be running all night regardless of the temperature. Whereas an electric heater will have a thermostat and will only come on when the temperature drops sufficiently. However, on the positive side, Paraffin heaters do produce CO2 which your plants will love! A paraffin heater is by far the most sensible option.

For more tips about heating your greenhouse take a look at this article.

Name: Sarah Griffiths

Question: Hi. When is the best time to cut down/prune sedums? Mine are looking very brown and pathetic now! Thanks

Answer: Hi Sarah. You can prune your sedums now if they have started to die back. Cut them back to about an inch above ground level. In particularly cold areas, some people prefer to leave the stems intact until spring to protect the crown from cold winter weather. But sedums are perfectly hardy so this should only be necessary if you normally experience extreme winter conditions.

Name: Wendy Johnson

Question: I purchased a Clematis named WILLIAM KENNET. I have had three blooms from it, do I need to cut it back for more blooms next year.

Answer: Hi Wendy. Clematis ‘William Kennet’ is a large flowered hybrid that falls into the Group 2 pruning group. These cultivars bear flowers on new shoots that emanate from the previous year's stems in late spring and summer. Some cultivars will produce a second flush at the tips of the current year's growth in late summer and autumn.

It’s definitely worth pruning your plant to encourage more blooms next year. Prune your clematis in spring before it starts into active growth. Remove any damaged or dead stems and reduce the remaining growth back to a set of strong healthy buds. New flowering stems will be produced from this framework of previous growth. Hopefully, with maturity and proper pruning you will have lots more flowers in the coming years.