Thompson & Morgan
Facebook Q&A Session 7th February 2014

 

Thompson & Morgan Facebook Q&A Session 7th February 2014 - Your horticultural questions answered.


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Name: Tim Davies-Moss

Question: When is the best time to plant trailing begonia tubers for baskets if I have no greenhouse?

Answer: Hi Tim. The reason that Begonias are generally started off in the greenhouse is that they require good filtered light, and this is best achieved in a greenhouse with the use of some shading to prevent scorching as the weather warms up. However, if you have a conservatory or a bright windowsill in a cool room then you can just as easily start them off in your home.

If you are growing them in your home it’s advisable to delay planting your tubers until mid March or even April. The light levels will be better by then so there will be less risk of brittle, leggy growth developing. By the time they are ready to plant into baskets, you should be able to move them to a protected spot outside. Just keep an eye on the weather for any late frosts, as you will need to bring them back indoors to protect them.


Name: Sarah Jackson

Question: When would be a good time to lift and relocate oriental poppies? Bought 2 as tiny root tubers years ago, and they have spread too close to a plum tree. They produce fabulous red flowers each year, and they deserve a more prominent place!!!

Answer: Hello Sarah. Your poppies sound fabulous and will definitely benefit from being divided. Your Oriental Poppies can be lifted and moved this Spring. March is normally a good month to move perennials as the soil tends to be workable and the weather is starting to warm up a bit.

Simply lift them with a garden fork, taking care not to damage the roots. Shake off any excess soil before replanting them in their new positions. Make sure that you replant them immediately to prevent the roots drying out, and give them a good long drink afterwards to help settle them in. I would suggest that you leave a few behind in their current position though, as they are clearly thriving there.


Name: Julie Atkinson

Question: Hi Sue. We have a Rebutia muscula cactus that has grown a few inches since autumn, but unevenly. It looks like it has grown too fast and the new growth is very thin compared to the rest of the plant. What can we do to resolve the growth? Thank you.

Answer: Hi Julie. From your description of its growth, I’m guessing that your Cactus is probably growing on a windowsill in a heated room. Unfortunately the low winter light levels and warm temperatures will cause rapid, weak growth. You will often see cacti with a ‘bottleneck’ and these growing conditions are generally the cause.

Rebutia muscula needs a cool, frost free winter temperature of around 10C during the winter months to ensure that it has a proper winter rest period. They should be kept virtually dry throughout the winter, only watering to prevent the roots from completely drying out. This reduction in temperature and moisture should initiate dormancy. Provided that the plant is dormant then it won’t need much light. With light no longer being a critical factor, this makes it much easier to find a suitable overwintering location - a frost free garage, unheated conservatory, or even a cool spare room.

I would suggest that you move your Cactus to a cooler position to slow its growth rate. Growth will resume in Spring as temperatures increase and your cactus can be returned to a brighter spot, and watering can be resumed. Given sufficient light this summer, you may find that it will even ‘outgrow’ the weak looking growth. Best of luck with it Julie.


Name: Ellie Bromilow

Question: I would like to ask about seeds, after watching the One Show today they showed some plants that were grown from seeds that were thousands of years old! The ones I have that are out of date are not that old but I wonder if it’s worth bothering trying to grow them? (I didn’t put them in the seed box. I have and found them in the sideboard when tidying) they are all Thompson & Morgan ones in one envelope but I know they must be at least 5 years old because I moved to Colne and I am sure I had these before then! They are Polemonium, Monarda, Delphinium, Red Hot Poker, Scabiosa, Campanula - are they worth having a go and trying to grow?

Answer: Hi Ellie. It’s always fun finding old seed - and it sounds like you have the makings of a lovely cottage garden with those perennials! Old seed will often still germinate but the success rate is likely to be reduced. Some seed, such as parsnip, lose their viability rapidly so it is worth buying new packets each year to avoid a disappointing germination rate. However, your perennials should definitely be worth a go. It doesn’t matter that they weren’t stored in a seed box - so long as they were kept cool and dry. Let us know how you get on Ellie.


Name: Jonathan Pollard

Question: I have a deciduous climbing hydrangea which was climbing up a fence panel that has blown down over the winter. I intend cutting it back while I repair the fence. Is it possible to take cuttings and if so what is the best way to do so? With thanks.

Answer: Hello Jonathan. Climbing Hydrangeas are best propagated by layering rather than hardwood cuttings as this technique lends itself to the plants natural growth habit.

When you prune it back, try to leave a flexible young shoot that you can bend down to ground level. Make a small slanting incision on the underside of the stem at a leaf joint. Dig out a shallow trench and peg the stem into the trench at the point of the incision using a small loop of wire. Press the stem downwards so that the incision opens up. Backfill the trench and water the area to settle the soil. By next autumn this section of the stem should have rooted and you can sever it from the parent plant and lift it for replanting elsewhere.

Just a word of warning about pruning - Climbing Hydrangeas can be hard pruned in spring to leave just the main framework of branches, but they may not enjoy this treatment and flowering can be reduced for a few years as a result. Best of luck propagating.


Name: Edina Adams

Question: Can I move my Asparagus plants? They are spring planting ones and this is their 3rd season. Had a few spears last year and hope for a full crop this year. They were the first thing I planted on my allotment and now I am more sorted I think they need to be in a better place.

Answer: Hi Edina. Don’t underestimate this job - it will be hard work! Asparagus roots tend to mat together as they grow making them difficult to move. However, if you have a new site well prepared then you could carefully lift them this spring while they are still dormant.

Choose a sheltered position in full sun. Asparagus beds should be richly fertile and well drained. Remove all weeds, and incorporate plenty of well rotted manure or garden compost into the soil to improve soil structure and fertility. On cold, wet soils the addition of sharp sand or grit will help to improve drainage. Try to cause as little disturbance to the roots as possible, lifting them gently with a fork and shaking away any excess soil before replanting.

It’s worth noting that Asparagus crowns are slow to establish and by moving them now you will almost certainly reduce your crop for this year. Best of luck Edina.


Name: Jenny Doyle

Question: Ask her what her one perennial, shrub and annual would be in her garden, and why.

Answer: Hi Jenny. What a lovely question, but difficult to answer - there are so many wonderful plants that it’s hard to pick just a few. Instead I’m going to tell you about the favourites that are already growing in my garden!

I love Hydrangeas but have a small garden, so I have chosen a simple and elegant variety with a reasonably compact habit - Hydrangea macrophylla ‘Madame Emile Mouillere’. It has rounded white blooms that gently flush to a delicate shade of palest pink and wonderful autumn foliage. I believe I picked this up from Christopher Lloyd’s garden at Great Dixter during a lovely summer visit with some old college friends.

I’m going to choose two favourite perennials, but that’s because they look fabulous together. Is that allowed? The combination of Stipa tenuissima and Helenium ‘Moerheim Beauty’ makes a wonderful display in my hot, sunny border. Stipa is a wonderful grass for adding movement to a planting scheme. It does seed about terribly but the seedlings are easily spotted and plucked from the soil if they aren’t required. The beautiful rust coloured flowers of the Helenium rise just above the Stipa to add a wonderful splash of colour to the scene. I find that this Helenium copes surprisingly well with my dry soil once it is well established.

For a favourite annual I would have to choose a Sweet Pea mix - a colourful blend of heirloom Grandiflora types with plenty of fragrance such as Sweet Pea ‘Heirloom Mixed’. I’m not too worried about the size of the blooms, but I find the scent of sweet peas simply heavenly!