Thompson & Morgan Facebook Q&A Session 19th August - Your horticultural questions answered.

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Name: Heather Martin

Question: Looking for ideas! Help! My mother-in-law will be 80yrs old in September and wants each bit of the family to take on a hanging basket or plant container in her garden. She would like some of the plants/flowers to be winter flowering. She lives in West London (riots haven't reached her yet). Any suggestions?

Answer: Hi Heather, what a lovely idea! There are a few container plants which will flower in the winter although it’s a good idea to use evergreen plants too, to bulk the container out and create interesting textures and heights. Good winter-flowering plants for containers include heather, snowdrops, hellebores, pansies, violas and primrose varieties such as ‘World's Most Scented Mix’.

Good evergreen plants for structure and colour include dwarf conifers, Euonymus, dwarf Hebes and cordylines. Many of these shrubs have colourful foliage which can be used to compliment the flowers. Heathers, Thyme and Gaultheria procumbens are evergreen and have good spreading habits so are great for trailing over the sides of a container.

Small varieties of grasses such as Carex flagillifera and Carex comans will spill over the sides of a basket or container providing a trailing effect. Other good trailing plants include ivy and periwinkle (Vinca). Hopefully this has given you a few ideas to help your mother-in-law get a good display! Good luck Heather, let us know how you get on.

Name: Christina Goozee

Question: One of the peach trees bought earlier this year finally burst into life but now loosing leaves to something. What do I need to clear it up please?

Answer: Hi Christina, there are a few pests which might chew the leaves of a peach tree. Earwigs are particularly partial to apricot and peach foliage and as the holes have appeared in the centre of the leaves, not just around the edges, I think they would be the most likely candidate. Earwigs are active at night so you’re unlikely to spot them doing the damage during the day. To diagnose if this is earwig damage, place a pot loosely stuffed with straw or shredded paper upside down at the base of the tree. Earwigs will hide in the pot during the day so you should find them there in the morning.

If you do find earwigs you can either keep emptying the pot each day and destroy them, spray them with an insecticide at dusk when they are active, or spread ant powder around the affected area. Although earwigs can be a pain they are actually beneficial to the garden too! They eat small insects and eggs so are a good natural pest control. I hope this helps, let us know how you get on.

Name: Alice Hartshorne

Question: Help cabbage caterpillars are destroying my winter crop of brassicas what can I do to stop them?

Answer: Hi Alice, I know how frustrating these pests can be! If you prefer to grow your vegetables organically then it’s best to pick the caterpillars off by hand and crush the clusters of small yellow eggs on the underside of the leaves. Make sure you check the plants regularly as the butterflies may still be laying eggs at this time of year.

You can also use nematodes, small parasitic worms which infect the caterpillars and kill them. It is perfectly safe to use on edible crops and is harmless to children, pets and wildlife. If you don’t mind using chemicals then there are quite a few sprays available in garden centres which will state on the bottle which pests they are effective against. I have found the best method of control is to net all my brassicas with a fine mesh, preventing the butterflies accessing them! Make sure you use a mesh with holes no bigger than 7mm - it’s surprising how the butterflies can squeeze into even the smallest gaps. I’ve found netting very effective and a lot easier than picking the caterpillars off by hand each week. I hope this helps Alice, best of luck.

Name: Liz Smith

Question: I have inherited 3 Lewisias from my mum, finally after 6 years of waiting 1 has flowered. What do I need to do to encourage the others?

Answer: That’s great news Liz - It’s always worth the wait when a plant finally flowers and often it’s simply a case of letting them reach maturity. If one is already flowering then the others may well follow suit next year. Sometimes all that is required is a little more patience. Your Lewisias originate from North America in open stony meadows and among rocks and crevices so they require excellent drainage and good protection from wet winter weather when grown in the UK. They are perfectly hardy so they can stay outdoors throughout winter, but if you are growing them in pots then you could move them against a protected wall to keep the worst of the rain off of them.

Lewisias survive in fairly thin soils so they don’t require a lot of fertilizer. If they are looking tired then it may be worth giving them a weak solution of liquid fertiliser, but don’t feed them unnecessarily. Hopefully next year they will all flower for you.

Name: Angela Lee-Smith

Question: Will citrus fruit trees grown from pips only about 2 inches high yet survive outside in the winter in Kent.

Answer: Hi Angela. Mature citrus trees are capable of surviving brief periods below 0C, but are best grown in large containers and moved indoors to a bright frost free position from autumn to spring, given that winter temperatures in most parts of the UK tend to drop below freezing point. Citrus seedlings are unlikely to survive even brief periods at this temperature and should certainly be over wintered in a frost free greenhouse or on a bright windowsill indoors.

Name: Roy Julian

Question: OK this might sound stupid but I has started some durham early would i be able to plant where i have grown cabbages this season or where i intend to grow next years crop. I did say i am new to this

Answer: Hi Roy. Cabbages are prone to the disease ‘clubroot’ and so it is normal practice to rotate crops to avoid this and other diseases from building up in the soil. You will therefore need to transplant your young cabbages into the bed that you intend to grow them in next year. If you still have a crop growing in that bed at the moment then you may need to pot up your cabbages and grow them on for a short while to prevent them becoming rootbound until you are able to transplant them into their final positions. Hope this helps Roy.