Thompson & Morgan
Facebook Q&A Session 23th March 2012

 

Thompson & Morgan Facebook Q&A Session 23th March 2012 - Your horticultural questions answered.


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Name: Steve Linden Wyatt

Question: Do you have any tips on growing roses over an arch? I have two lovely climbing roses and I know it is early but the cover is not great despite them being there for two years. I have got height just not width.

Answer: Hello Steve. This is a very common problem with climbing roses which love to do just that - climb! If left to grow naturally they will often produce tall stems, but fail to form any shoots lower down on the plant. The result is that the flowering shoots will all be at the top of the plant leaving the lower part of the plant bare and unattractive.

You can encourage your climbing rose to produce side shoots lower down by tip pruning the tops of the stems this spring. The secret to encouraging roses to flower low down on the plant is to train the main stems horizontally (or as close to horizontal as you can), to encourage the dormant buds to break and produce flowering side shoots. This may mean twisting them around their support or criss-crossing the stems so that they are at diagonals to one another. If the stems are not particularly flexible then you may need to settle for just training them up the arch in an hour glass shape. Tie the stems into their support and if possible, tie the top of the stem so that it is pointing downwards. This should encourage much better flowering lower down on the plant. You can also give them a good mulch with some well rotted manure to give them a boost this summer. Hope that helps Steve.


Name: Angela Lee-Smith

Question: A question for Sue's question and answer session. I have cats and use wood capsules for their litter tray indoors when they use it, it turns into sawdust is this any good for making compost.

Answer: Hello Angela. Sawdust is great for your compost heap - treat it as a brown material (such as cardboard or dry leaves) that will add carbon to your heap and balance the nitrogen levels from food waste and grass clippings. However you should only use the sawdust - avoid adding larger wood pellets as these will take much longer to break down. You also need to take care not to add solid cat waste to the pile, although urine will be fine! Hope that helps Angela.


Name: Heather Nelson

Question: We sawed up all our wood, and now have a huge bag of sawdust; can I use it as weed control on the garden?? Or what would anyone suggest??

Answer: Hello Heather. If you are referring to sawdust or wood shavings then please see my answer to Angela above. However, you should avoid putting larger pieces of wood into your compost heap. If you have pieces that are the size of bark chippings then these can be used as a mulch or for an attractive top dressing on containers.


Name: Yvette Britton

Question: Any thoughts on what is eating my daffodil buds and flowers please? We seem to have a major problem this year. Hope you can help.

Answer: Hello Yvette. It’s hard to say without a picture but my bet is that it is slugs or snails that are causing the damage. Try popping out with a torch one night and take a look to see if you have a thriving colony of them! Daffodils can occasionally be trouble by birds as well.


Name:BaronPeter Jagerbomb Dixon

Question: I have a question. Will carrot fly harm my tomatoes when I put them outside as they will be close to each other?

Answer: No, Carrot fly should not be interested in your tomatoes at all. Carrot fly larvae feed on carrot roots and sometimes parsnips, celery and even parsley - but not on tomatoes.


Name: Eunice C English

Question: What can I get for a Mediterranean courtyard for a screen please? I rent my flat so don't want to spend too much. I've got lavender in the garden but want something tall in a pot that can take gusty winds?

Answer: Hi Eunice. That’s quite a tricky one as there are not many tall Mediterranean plants that will tolerate the cold, gusty winds we get in the UK. Have you considered Escallonia? There is a variety called ‘Apple Blossom’ that is quite pretty. They are tough shrubs that can be grown in a container and tolerate exposed conditions well. Pyracanthas can produce wind tolerant screens too. If you would prefer a climbing plant then consider a rambling rose that can be trained against a trellis to produce a screen. Even large flowered clematis varieties will often tolerate quite a lot of wind - and these can be trained onto trellis or an obelisk to provide height. I hope that gives you some ideas to get started with.


Name: Sheila Whiles

Question: I have found these in 3 hanging baskets & 3 container pots. 1 pot only had 1 New guinea busy lizzie in. The other hanging baskets had Geraniums, Million Bells petunias and begonias. One pod had split and a green shoot had appeared. I have found 20 of these all different sizes. I have planted 5 in a pot but it takes so long and I would like to know now. The compost used was from different bags and 1 basket had old soil in. Thanking you for your time.

Answer: Well Sheila - this is a bit of a mystery! Until they germinate and grow a little it will be difficult to identify them I’m afraid. Certainly the seeds that you photographed do not come from any of the plants that you have mentioned. My first thought is that there may have been a plant overhanging your containers that has dropped its seed into your pots. It may not even be from your garden - perhaps something from a neighbouring garden?

My second thought is that these seeds may have been deposited there by birds or even mice, so they could have come from anywhere in the local area! It will be fascinating to see what they become. We would love to see another picture once they have grown.


Name: Nadia Brasher-Wiltshire

Question: Ok my bay trees have turned brown. I’m not a great gardener only got these at xmas. I really don’t want them to die. Please help xx Oh dear Nadia - that doesn’t sound good. You can check to see if they are still alive by scraping back a small piece of bark on the stems with your thumbnail. If they show green underneath then they are still alive.

Answer: Bay trees are fairly hardy once established, but young plants can easily be damaged by frost. If you notice that the tips of the stems have sustained most damage (particularly toward the top of the plant where the leaves and stems are more exposed) then frost damage is the most likely cause. If your plants are in containers then you could move them to a sheltered position on frosty nights, or throw some fleece over them to protect them. You can pick off any dead leaves this spring - the stems will often leaf up again as the weather warms. Give them some time to recover this summer. If no buds appear by late spring then the bare stems will need to be cut back to live wood. Bays can tolerate hard pruning but are quite slow to recover so it is best to avoid this unless necessary.

It’s also worth reviewing the soil that your plants are growing in. If containerised then they could be suffering from drought - yes, this can even be a problem in winter! Check that the compost has not become overly dry. If so, you will need to give them a good soaking, and thereafter try to keep your plants consistently moist. Good luck Nadia.

Name: Hazel Ryland-Cole

Question: Carrot fly. I use "resistant" seeds, and have Environmesh (though it looks dreadfully untidy in such a small garden as ours) but still get problems. I remember watching Monty Don on the television sowing carrot seeds, commenting about sowing at a particular time of year - late in the season I think - to miss the carrot fly life cycle. Can you advise? Where can I learn more about the carrot fly life cycle?

Answer: Hello Hazel. Overwintering larvae will pupate in the soil and emerge as adult flies in May and June. The female carrot fly is attracted by the smell of carrots and lays its eggs in the soil, close to your crops. These hatch as larvae (orange-white maggots) after about a week, which survive in the soil by feeding on the carrot roots for about a month before pupating in the soil. In August and September a second generation of adult flies will emerge from the soil and once again lay their eggs close to your carrot crops. These will hatch into larvae that will overwinter in your soil until next year.

I think that what Monty Don was explaining is that you can time your crops to try to avoid periods when larvae are active in the soil. You can avoid the first attack by delaying sowing until late May when the first generation of larvae have already emerged as adult flies. Sow seed thinly to avoid the need for too much thinning as your seedlings grow. Also, when thinning seedlings, take care not to bruise the leaves as these produce a scent that will attract female carrot fly. You will need to remove the thinnings from the plot immediately and water your crop thoroughly to disperse the odour.

Hopefully this will reduce crop damage but I would still recommend using an Environmesh barrier. Make sure that it is at least 18 inches high and partly embedded into the soil. You should also cultivate your soil thoroughly in winter to disturb the overwintering larvae and expose them to hungry birds. I hope your carrots are more successful this year Hazel.