Thompson & Morgan Facebook Q&A Session 30th September - Your horticultural questions answered.

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Name: Damon Lowes

Question: I received patio apricot tree last year (aprigold). In early spring just before flowering, i placed it into my bubble wrapped greenhouse. It flowered, but got no fruit and all looked well with the tree. Once I took it out of the Greenhouse, it started to deteriorate, with the leaves turning brownish (still greenish) and folding over on themselves. The leafs are now starting to fall. Do you know what is wrong or how I can help it next year?

Answer: Hi Damon. There are two major reasons why your apricot tree might not have fruited. Firstly, it may simply not be mature enough. Like all fruit trees, apricots are unlikely to produce fruit for at least 3 years but may take longer depending on the growing conditions and variety. The other possible reason is that the flowers were not pollinated. This can be a problem in a greenhouse where there a fewer pollinating insects but you can improve the chances of pollination by simply opening the greenhouse door each day. You can also try hand pollinating by gently tickling the centre of each flower with a small paintbrush.

The leaf damage that you describe could be Peach Leaf Curl which is a common fungal infection of prunus species including apricots. If you noticed any red blistering on the leaves and die back of branches then that would confirm the diagnosis. Once the symptoms of peach leaf curl are spotted in spring it becomes very difficult to treat the problem, so most treatments for peach leaf curl are preventative rather than curative. The fungal spores of peach leaf curl require moisture to germinate, so this infection occurs particularly during wet spring weather.

You will need to spray your apricot this autumn and again in February with a copper based fungicide. I would suggest that you follow up your February spray with a second application about 2 weeks later. Keep your apricot under cover from late winter to May to keep the spring rains off, thereby preventing the spores from germinating, but make sure that you ventilate your greenhouse as the days warm up in spring. Hope this helps Damon. Better luck next year.

Name: Shaun Osborne

Question: I have discovered that some of my young broccoli leaves have gone like thin and near transparent. Someone told me this is caused by leaf mining insect. What do you suggest to treat it?

Answer: Hi Shaun. Leaf miner is a generic name that is used to describe the larvae of lots of different species of flies, sawflies, moths etc that feed on leaf tissue. Because they tunnel though the inside of the leaf, the damage is characterised by a maze of winding silvery trails or blotches where the leaf has been hollowed out (thus making them appear transparent). The easiest way to control them is to simply remove the damaged leaves and squash the larvae inside.

Name: Sharon Chaplin

Question: Hi. This year I bought 5 geranium tubers and 1 begonia, and would really like to see if I can keep them for next year, as they are both so beautiful. I have been reading articles online about over wintering them, but wondered if anyone on here could it explain the process in easy terms to me?! Thanks

Answer: Hi Sharon. By geranium tubers, I am assuming that you are referring to bareroots which you would have bought without foliage, and planted below soil level. If so, then these should be hardy perennials and will be fine left outdoors in the ground over winter. The foliage will die back this autumn but it will re-grow next year.

However if you received your plants as plug plants then they are probably half hardy and will need winter protection. If they are planted in the ground then you will need to gently dig them up taking as much of the root balls as you can, and replant them into pots of multipurpose compost. Water the plants and place them in a bright, cool (but frost-free) greenhouse or conservatory. During winter keep the compost on the dry side to discourage rotting. You can plant them out again after the risk of frost has passed in May next year.

Your begonias will definitely need protection, but as with the geraniums, it helps to know what type you are growing. Some begonias produce tubers below ground while others do not. If you received your begonias as tubers then you will know that these are tuberous types. If your variety of begonia is tuberous then reduce watering it as the foliage starts to die back and gradually allow the compost to dry out. Alternatively lift the plant from its container, clean the tubers and lay them somewhere dry and frost-free to allow the foliage to die completely. The dead foliage can then be removed and the tubers stored in containers of dry sand or peat (or even in paper bags) somewhere cool and frost-free. Keep them at a temperature of 5-10C.

If your Begonia is not a tuberous variety then simply bring it indoors to a bright, cool and frost-free position (a slightly heated greenhouse or bright windowsill is ideal). Water sparingly as Begonias are susceptible to stem and rhizome rot. You can plant it back outside in late spring after the risk of frost has passed.

If you let me know the names of your begonias and geraniums then I can tell you which type they are which will make it much easier to decide how to look after them.

Name: Russell Lilley

Question: Tempted to get a mushroom kit, before I do any tips on how to keep the flies away that the kit attracts?

Answer: Mushroom kits are particularly attractive to flies as they like to lay they eggs in the soft compost. One tip that I have read is to coat the upper part of the compost bag with a thin layer of vegetable oil. Apparently it works like fly papers and they stick to it. Not sure how effective this is but it’s worth a try!

Name: Saffron Gardenchild

Question: How much room do you need to grow mushrooms, realistically?

Answer: There really isn’t a specific answer to that question Saffron - it depends greatly on what type of mushroom you want to grow and on what scale you want to do it. Mushroom beds can be built in cellars and sheds and will need to be 25cm (10") deep but there is no limit on the length and width of the bed. These are great for growing button mushrooms such as White caps and Brown caps. If you don’t have much space then you will probably prefer to grow them in a smaller box - say 45cm (18") x 45cm (18"), but it will still need to be about 25cm (10") deep. The other option is to try growing oyster mushrooms on straw bags. These won’t take up much space - they should fit in a bucket.

For more exotic species such as Shiitake mushrooms you can grow these on logs outdoors. The perfect spot is a wooded shaded area or in a damp spot beneath an evergreen shrub so they needn’t take up much space at all!

Name: Tracey Williams

Question: Can anyone tell my friend what this is? Its originally from Turkey.

Answer: Hello Tracey. It looks like Caesalpinia gilliesii. We don’t sell this particular species but we do sell Caesalpinia pulcherrima. It’s a tender shrub so it will definitely need winter protection.

Name: Phoebe Isabella

Question: I'm taking down all my flower pouches soon, and the soil in them is rigid with roots - if I cut off the plants can I compost them over winter and re-use the soil the next year, when the roots have rotted down a bit? Or do they just get binned?

Answer: Hi Phoebe. The soil is really best broken up and added to the compost heap. After a full growing season there won’t be many nutrients left in it so you will certainly need to use fresh compost next year.