Thompson & Morgan Facebook Q&A Session 28th April - Your horticultural questions answered.

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Name: Anna Mason

Question: Hi T & M - ANTS!!!! Ok last year I lost an acer in a container and when exhumed from its pot the whole root ball was a massive ants nest. This morning my posh paving at the front is Vesuvius of Ant dirt. I have watered in an Ant Killer but they have invaded a pot full of Polyanthus and Pansies. The Acers will be next what I can do please.

Answer: Ants can be a bit of a nuisance in the garden but it is unlikely that they were the cause of your Acers death. They are generally quite beneficial in the garden as they feed on sap sucking aphids and the honeydew that they produce.

You could try applications of ant deterrent and watch to see where they move to. If you keep applying it wherever they move, then sooner or later they will find somewhere to live which will be less of an inconvenience to you. Applying broad greasebands or gluebands around base of your containers may help to discourage them from setting up home in your patio pots. It is also well worth encouraging insectivorous birds to your garden who will help to keep the ant population down. You should try to keep aphid infestations under control in your garden too, as aphids provide an excellent food source for ants - ants will even ‘farm’ aphids in order to harvest the sugar rich honeydew that they produce!

Alternatively there are chemical ant killers on the market that can be used to good effect. If you are determined to kill them then you may want to use chemical bait that is taken back to the nest and shared among all of the ants, thereby ensuring that the nest is completely destroyed. You can pick this type of ant control up at most garden centres. Hope that helps Anna.

Name: Ellen Kunec

Question: Good Morning T&M! WRT The Pinova apple tree that is not self pollinating, there are apple trees on my allotment site but none on the neighbouring plots so my Q s: would it produce fruit on my allotment? Thank you.

Answer: Hi Ellen. Apple trees should normally be planted within about 30m (100 ft) of one another to ensure regular visits to both trees by the local bee population. At this distance you should still get a decent fruit set on your apple tree.

Name: Matthew Eddy

Question: My tomato plant leaves are not looking very green but a light yellow is this normal and do you want a picture of them?

Answer: Hi Matthew. It sounds as though your plants may be suffering from a magnesium deficiency which is quite common in tomatoes. The leaves turn yellow but the veins remain green. This is caused when magnesium becomes locked up in soil where potassium levels are high. Try an application of magnesium sulphate or Epsom salts to correct the problem. You may need to repeat the treatment but hopefully this will solve the problem.

Name: Matthew Eddy

Question: I have used weedkiller on the weeds in my lawn but the grass has gone yellow. What can I use to bring the grass back? Grass seed or an aftercut product.

Answer: Hi Matthew. It’s easy to overdo the weedkiller and affect the lawn too - don’t worry, you are certainly not alone with this problem! I would suggest that if it is just a few small patches then you could dig out the affected areas, apply some fresh soil, and reseed the affected patches.

However if this problem has affected the entire lawn then this would suggest that the lawn had been scorched by the product that you used on it. There are no real quick fixes I’m afraid. Keep it really well watered and you should start to see some regrowth. Once the regrowth begins you can apply a feed later in the season to help it along. In future I would recommend that you always ‘water in’ any products that you use on your lawn to prevent them scorching the top growth.

Name: Dam Hg

Question: Zinnia Zahara Starlight Rose: where are those pink brush strokes for that I bought this seed from T&M? Is there something wrong in my soil or fertilizer? Oa oa oa... Just a tiny tint of pink at the end of the petals. I should kill myself. oa oa oa Or should the pink grow more each day?

Answer: Hello Dam. Don’t worry. Your plant should start to produce better coloured flowers as it matures. Sometimes the colour doesn’t show on the earliest flowers but this will improve as the season goes on.

Name: Anna Mason

Question: Hi T & M i posted some pics in an album but no one has responded. My clematis are looking sick at the base. This has only happened to 2 out of 4 plants. Basically the bottom leaves go yellow then shrivel up and go brown and crisp.

Answer: Hi Anna. I must admit that it is very difficult to see what the problem is from your picture. It is normal for plants to shed leaves as they age, particularly those at the base of the plant that are starved of light. However, I notice that only some of the leaves are affected - have you checked whether this problem affects all of the stems or just a single stem? If it is just a single stem then you will need to investigate it much closer to determine what the cause of the problem is (mechanical damage, pest damage, virus etc.) It may need to be pruned out entirely.

Clematis can form quite large root systems and will use a surprising amount of water so it is always beneficial to give them plenty of room to grow. If the plant is at all root bound then you will need to repot it in fresh compost. Regular feeding and watering will also help to promote healthy new growth, but take care not to over water as they dislike a waterlogged soil. If you are able to provide any further information that might help to form a diagnosis, please let me know.

Name: Lucy Garden

Question: A question for Sue - I'm pretty sure my young apricot tree has canker. It flowered beautifully but all the twigs that flowered have now died back and some have oozed gum. This happened last year too and I only had 2 or three fruit - this year I doubt I'll get any. Can the tree be saved? It's growing well in the places where the twigs didn't die, but I fear the same thing will happen next spring. If I buy a new tree, will it get infected too?

Answer: Oh dear Lucy. It doesn’t sound good! Bacterial canker commonly affects members of the prunus family causing sunken lesions in the bark in spring which is often accompanied by oozing gum, and small holes in the leaves from early summer.

Unfortunately once canker has infected the tree in spring there is little that can be done to save your crop this year. Prune all infected wood from mid to late summer back to healthy wood and paint the pruning cuts with wound paint to prevent bacteria re-entering the wounds. Apply a copper based fungicide in autumn as the leaves fall, and repeat this application several times throughout the winter. This should help to prevent a recurrence of the problem next year.

However, if the tree is particularly badly affected then you may wish to replace it. It would be preferable to plant your replacement tree in a different location. But if this is impossible then I would recommend getting into the habit of spraying your replacement tree with copper fungicide in autumn and winter as a preventative measure. Let us know how you get on Luci.