Thompson & Morgan Facebook Q&A Session 14th October - Your horticultural questions answered.

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Name: Ilya Burkin

Question: I want to plant a honeysuckle in a container and put it on balcony so it can hang down. What sort of honeysuckle would you recommend or they all are climbers?

Answer: Hi Ilya, honeysuckles can either be twining climbers or shrubs but unfortunately there are none that naturally trail. If your balcony has railings the honeysuckle will immediately try and climb up them. It’s best to provide a support such as an obelisk or bamboo poles.

Honeysuckles will perform better if grown in the ground but if you do decide to grow one in a container, make sure you choose a large pot (no smaller than 45cm (18in) diameter and depth) as these plants have extensive root systems. Choose soil-based compost such as John Innes No. 2 or 3 to fill your containers rather than multi-purpose compost. Every 3 years you will need to either pot up the honeysuckle to a larger pot or prune the roots and place the plant in fresh compost. Feed the honeysuckle annually for the best flowers and foliage, and make sure the compost stays moist as honeysuckles will suffer in dry conditions. I hope this helps Ilya, good luck.

Name: Louise Phelps

Question: After some advice - I've got a small copse of native trees at the edge of my lawn and the grass extends under the tree cover. What's the best way to remove the grass and prep for planting shade loving varieties (heuchera, ferns, geraniums, foxgloves, hellebores etc)?

Answer: Hello Louise, the best way to tackle this will be either digging by hand or by placing black polythene sheeting over the desired area. Assuming you wish to keep part of your lawn, weed killers would be undesirable as they may damage the part you want to keep. I would start by defining the area of grass you wish to remove and where you would like the existing lawn to finish. To make a neat edge to your existing lawn I would use something like a lawn edging iron.

If you can wait until next spring to plant your shade-loving plants then you could use black polythene sheeting to smother the grass. Make sure the edges are pegged down so that no light can penetrate. This should hopefully be enough to kill the grass. Alternatively, as you will have to dig the area anyway, you could remove the grass by hand. If you push a garden fork in to the grass and lean it back slightly it will gently loosen the roots and soil. Repeat this over the whole area without treading on the forked areas. Subsequent lifting of the grass should be a lot easier after loosening the soil. Take care if you are digging near the trees, to try and minimise root damage. I hope this helps Louise, it sound like your efforts will be worth it!

 

Name: Phoebe Isabella

Question: Q for the Friday answers session - my Christmas cactus leaves are going a dark red, is this due to not enough or too much watering? It's in a conservatory but there is daily ventilaton and the blinds are drawn to stop direct sunlight. This has only recently started to happen, the cactus is hears old and has never had any problems......

Answer: Hi Phoebe, red leaves on Christmas cacti (Schlumbergera) could be a sign of waterlogging, drought, nutrient defiency, or a reaction to changing temperatures and light. If the colour change is due to temperature or the shortening day lengths then the effects won’t be permanent and won’t harm the plant. You could start by turning the plant out of its pot and looking to see if the roots are white and healthy - the soil should be damp, but not wet. If the compost is wet, try reducing the frequency of watering; if dry then provide more water. Unlike desert cacti these succulents actually prefer a consistently moist soil, particularly when they are in active growth.

Your Christmas cactus will also need some nutrients, particularly if it has not been re-potted for some time. If the roots look very congested then re-pot it into a slightly bigger pot. Feed your Christmas cactus with any balanced fertiliser whilst it is actively growing (when it is flowering or growing new leaves). Hopefully if you provide your Christmas cactus with the right watering and feeding regime it will continue to flower for you for many years to come! Best of luck Phoebe.

 

Name: Helen Martin

Question: I need some help please!!! I have been give as a very special pressie a beautiful standard olive tree. Looks a bit like a bay tree. I live in the midlands so guessing in the winter I need to protect it from frost but beyond that have no idea how to look after it. Can anyone else help me please? Thanks xxxxx

Answer: What a lovely present, Helen! Olive trees are hardier than many people think and mature trees can tolerate cold periods down to -7C for short periods. In very mild areas, olive trees can be planted in the ground in any free draining, neutral to alkaline soil. Several layers of horticultural fleece will often be sufficient to protect them.

However in colder areas, including the midlands, I think it might be best grown in a large container of soil based compost such as John Innes No.3. This allows you to move it to a cold greenhouse or sheltered position during the winter months. You will need to keep watering to a minimum over winter so that the soil is kept moist but never wet, to prevent the roots from freezing.

In the spring you can move it outdoors again. Position it in the sunniest part of your garden.During the summer months feed and water it regularly. If necessary you can prune your Olive tree in late spring or early summer, removing misplaced growth to encourage new shoots. I hope this helps you Helen.

Name: Anna Mason

Question: Can I sow carrots in buckets now and grow them in greenhouse or conservatory and can I sow swedes and put a couple in each potato bag in greenhouse.

Answer: Hi Anna. I’m glad to hear that you are reusing your compost for a second crop. You can certainly sow carrots still. I would recommend an autumn sowing variety such as ‘Nantes Frubund’ that has been specially bred for sowing at this time of the year. As for the swede, I would wait until next spring as they are normally sown from April to June. But there are lots of other crops that you can still sow. Take a look at our Top Ten Vegetables to Grow Over Winter article for some inspiration.

Name: Shaz Whitfield

Question: Hi, I’ve had a cranberry plant for three years but up to now no cranberries, any advice would be appreciated.

Answer: Hello Shaz. Most fruiting plants will take a few years to mature before producing fruit and cranberries are no exception. Often it is just a matter of patiently waiting until they surprise you one year with a bumper crop! But in the meantime it is worth reviewing the growing conditions to make sure that you are giving it the best possible chance of fruiting.

Cranberries plants require moist but well drained, acid soil in a sunny or semi shaded position. If you don’t have acid soil then they are best grown in patio containers using a mix of ericaceous compost and John Innes No. 3. If possible, cranberry bushes should be watered with rainwater because the lime contained in tap water will reduce the acidity in the soil over time.

Cranberries are self fertile so you won’t need a pollination partner for your plant. When some fruits finally begin to develop, you will need to cover the plants with netting to protect the berries from birds. Hopefully you won’t need to wait too much longer Shaz.

Name: Catherine Johnson

Question: I have just harvested my sweet potatoes and there are several small tubers, can I leave these in the ground or store them to grow new plants next year?

Answer: Hi Catherine. Sweet potatoes are grown from slips (unrooted shoot cuttings) rather than from the tubers so you would need to encourage the tubers to produce shoots, then remove the shoots and pot them up to encourage root development, before you could plant them out. It’s a bit of a labour of love as they require high humidity and moist conditions. But if you like a challenge then you should store the tubers in a cool, dry place over winter and then start to sprout them in late February/ March.

Set the tubers out in a tray of moist sand or vermiculite and place them in an airing cupboard or propagator at least 26C/ 80F. You will need to keep a constant check on them to make sure that the sand/ vermiculite doesn’t dry out. They should begin to produce shoots which can be removed with a sharp knife when they are about 5 -7cm (2-3") long. Pot up the sweet potato slips and grow them on in warm, frost free conditions until they are rooted. When all risk of frost has passed, gradually acclimatise plants to outdoor conditions prior to transplanting them. But if that sounds like too much work then you can order some sweet potatoes from us. Good luck Catherine. Let us know how you get on.

Name: Clare Palmer

Question: Hellos :) Just a quick question... my tomato plant (which has been grown outside my home in Northern Ireland) didn't produce fruit all summer. I moved it round the side of the house, and now it is! When do I cut it back? And will it regrow next year? Also, my pumpkin plant was doing great, with lots of flowers, but it hasn't produced a pumpkin and, after some strong winds, now looks on it's way out - should I cut it back, or pull it up? Thanks for your advice!!!

Answer: Hi Clare. It sounds like your tomato was a late starter! Now that the temperatures are dropping your tomato is likely to start dying back, and the first frosts will certainly finish it off. Harvest what you can of your crop this month and then retire the plant to the compost heap. If there are green tomatoes on the plant then don’t waste these - they can be made into chutney!

Tomatoes are annuals so you will need to grow new plants next year from seed or you can buy them as plants if you prefer. There are lots to choose from so why not take a look at our range. Here a handy article for some extra growing advice.

I’m afraid that your pumpkin will also need to be thrown out as it is too late for it to produce fruit now. Unfortunately it’s been a bad year for pumpkins. But don’t be put off of trying to grow them next year though. Here are a couple of things that you can do to help them produce pumpkins for next Halloween. Firstly, make sure that they are planted in a really sunny site with 6 or more hours of direct sun a day. Throughout the growing season keep the plants well watered and feed them a high nitrogen fertiliser.

In cold seasons it may be necessary to hand pollinate pumpkins to ensure that they fruit. Female flowers have a bump behind the petals, whereas the male flowers do not so they are easily identified. Once you have identified a male flower, remove it from the plant and gently remove the petals. Then press is against the centre of each female flower. Alternatively you can use a fine paint brush to tickle the centre of the flowers with and transfer pollen to the female flowers. Better luck next year Clare.