August 2021: Amateur Gardeners Question Time “GQT”

Our amateur “GQT” was attended by over 50 members and OPG volunteers and was held outside, in the Peace Garden behind Charlton House.  Our president, Sir Nicolas Bevan, introduced the panel experts – guest panellist Joe Woodcock, plus Vija Vilcins and Pat Kane. It was an exceptional meeting.  As Sir Nicolas said, this was the first time members have met face-to-face since the beginning of the pandemic. To celebrate this it was also a social event with wine and nibbles provided – and appreciated!


Questions and Answers

Q1
Stella B: I would be grateful for some suggestions for a small or medium sized tree for my back garden. It’s a ’coming along’ garden begun a couple of years ago. There are now 3 apple trees (2 half standards and one espalier), so not another fruit tree. I really need it for some screening (it’s a terrace house) so maybe 12-15ft full grown? Not too wide a spread.

Q1 ANSWERS:

a) Joe: 

i) Although Stella was not keen on fruit trees the crab apple would be a good tree. e.g. Malus ‘Red Sentinel’ with its wonderful golden leaves.

ii) Japanese maples (Acers) e.g. Senkaki with  its yellow leaves in summer and its beautiful golden tints in autumn when its leaves become tinged with pink. Or Acer palmatum ‘Garnet’, a low growing acer.

iii) Rowans such us Sorbus acuparia and Sorbus ‘Joseph Rock’,  yellow flowers with superb autumn colour.

iv) The Handkerchief Tree (Davidia involucrata).  But maybe too large if the garden is small.

v) The Fox Glove Tree (Paulownia tomentosa).  Because it grows into a large tree, buy it young and coppice it. It will then grow into a low growing shrub with very large leaves.

b) Pat:

i) The Paper Bark maple ( Acer griseum) and the Snake Bark Maple(Acer capillipes).

ii) Amelanchier lamarkii.

iii) Prunus ‘Snow Showers’ which hangs down.

c) Viya:

i) Amelanchier.

ii) Cornus canadensis.

iii) Cercis canadensis ‘Forest Pansy’ with burgundy leaf.

Q2
Chris B: I was given a Geoff Hamilton rose at the end of May and it flowered beautifully, but there have been very few flowers since then. It is supposed to be a repeat flowerer. Is there anything I can do to encourage more roses?

Q2 ANSWERS:

a) Joe:
It’s a modern shrub rose. If bought in a pot it needs time to establish. The roots need tweaking out before planting and it needs time to acclimatise  to the soil and develop the  energy  for flowering and will very likely  flower better next year  when it has had time to acclimatise. In spring give it a mulch  and feed it with Tomorite.

b) Viya:
Referring to roses in pots she said she had  kept an Emma Hamilton rose in a pot and it needed a regular feed  because the soil gradually lost its nutrients.

Q3
Pat K: I’ve got scale insects on the trunk of my Viburnum bodnantense Dawn. It’s planted in a pot as no room in the garden. The best way to get rid of it without any chemicals, please?

Q3 ANSWERS:

a) Joe:
Using cotton buds with methylated spirit, and squish them! Systemic fertilisers have been mostly withdrawn nowadays. Ants may form nearby which harvest them, but they are harmless.

b) Viya:
She said she has used a fingernail scrub. A labour of love. But they didn’t come back.

Q4
Carolyn H: My clematis (several varieties) are covered in black fly this year. The flowers are also being eaten. Are these two problems related? Is it a particular problem this year? How can I prevent it happening in future. Three questions actually!

Q4 ANSWERS:

a) Joe:
He said that his clematis were the best they have ever been this year! But the black fly problem may be due to the weather conditions this year. Use a hosepipe to wash them off or squash them with your fingers. If you use chemicals use a fatty acid one not a systemic . They may have been eaten by slugs and snails. Well known ways of getting rid of these include using egg shells, beer traps and   wool. Also there is the book ‘50 ways to Kill a Slug’ by Sarah Ford.

b) Pat:
Go out at night with a torch and pick them off.

Q5
Kathy A: Do you have any suggestions or rules for how to space perennial plants out in a herbaceous border? I always start off ok but by about now everything looks squashed and lots of fighting for space going on. I was always told not to leave bare soil between plants as then you get weeds, but I don’t seem to be able to find that happy medium.

Q5 ANSWER:

a) Joe: I do the same. I suggest you cut back the thuggish plants in summer and make space for others. If it is a new border plant in odd numbers e.g. 3, 5, 7 etc. Fergus Garrett at Great Dixter has produced a video showing how to space out plants.

Q6
Melanie A:  I would appreciate some suggestions for plants to go in a shared space. This is the scenario: our houses are fortunate to share a fairly large open space for which the householders are jointly responsible. We keep maintenance costs to the minimum by doing much of the work ourselves. Some of the trees planted many years ago by some householders help shield us from the horrors beyond, but they cast a lot of shadows. It would be great to have some thoughts  on how to put some items of interest in this space, something that can’t be mistaken for lawn by enthusiastic mowers.

Q6 ANSWERS:

a) Joe:
In shaded areas plant Mahonia, Camellia, Elaeagnus and in damp shade ferns e.g Dryopteris wallichiana and Dryopteris filix-mas. Also plant in groups: Epimedium , Pachysandra terminalis, Pulmonaria  ‘Sisinghurst White’. Foxgloves (Digitalis) and Japanese anemones(e.g.Honore Joubert) to show up in the shade. Spring bulbs like Tulip Red Riding Hood and Tete-a-tete.

b) Viya:
Miscanthus which initially only needs minimal watering just to get it going. Also Nandina domestica and Hydrangea ‘Vanilla Phrase’.

Q7
Angela B: Have you any suggestions for getting rid of pond duck weed?

Q7 ANSWER:

a) Joe: You can never get rid of duck weed. But use waders and a metal rake to clear it. Do leave it on the side for a day so that any organisms in it that need to live  in the pond can return to it. Also, if new, place your pond near a bit of shade. Put in oxygenators and pond plants that will help maintain a balance such as irises and marsh marigolds(Caltha palustris). Try to maintain at least one third cover with lilies and marginals. Also a fountain would be useful.

Q8
Anne R:  I have a Sorbus (Rowan)  which I think is Sorbus ulleungenis ‘Olympic Flame’.  It’s about 8 years old and still quite small and every year some of its growth dies back. It’s in a north-by-northwest  garden, so it gets some sun, on heavy clay but well drained. Am I doing something wrong or is it the wrong tree for the space. I know I’m not the only person with a die-back problem I saw a Sorbus in Greenwich Park recently with the same problem.

Q8 ANSWER:

Joe: The rooting of Sorbus is vulnerable to extremes of environmental conditions. It doesn’t like heavy wet soil in winter and cracked soil in summer. Take a garden fork and lift and reduce compaction around the roots. Waggle the fork in the roots (“terra vent”). Mulch in winter. Monitor the tree and cut out dead wood.

Angela

OPG diary – August 2021

The Bank Holiday weekend was enlivened with a play “Family Tree” performed in the gardens, as part of the Greenwich & Docklands International Festival. Based on the life of Henrietta Lacks, it certainly lit up the garden!

'Family Tree' by Mojisola Adebayo, performed in Charlton House gardens as part of Greenwich and Docklands International Festival, August 2021

A very tall flowering plant which is just coming out in the garden has been catching the attention of visitors and volunteers alike. It is Vernonia arkansana ‘Mammuth’ and was featured this week on Gardeners World when Nick Bailey visited Knoll Gardens. Very appropriate as we bought our own Vernonia from Knoll Gardens back in May!

Together 21: Volunteers were in the garden for the borough’s Together 21 Festival. Very sad for visitors that it was such a drizzly day, but at least the garden liked all the water. Spirits not dampened but umbrellas were up!

CABAHS volunteer in the Old Pond Garden at Charlton House, August 2021

This is our bargain plant of the month – a Lysimachia clethroides specimen bought for £10 at Members’ recent trip to RHS Hyde Hall, and now split into 23 new plantlets. Filled up the whole corner of one bed, we are just so thrifty!

CABAHS volunteers dividing a Lysimachia in Charlton House gardens, August 2021
Old Pond Garden, Charlton House, August 2021
Persicaria amplexicaulis 'Firetail' in the Old Pond Garden, Charlton House, August 2021

A view of my garden is an excellent tonic!

Since my recent spinal surgery I have been frustratingly incapacitated. However who would not be cheered-up and consoled by a view like mine? From a prone position on my living room sofa I look out, through a huge glass sliding door, onto a beautiful panorama of colourful flowers. I had worked so hard in spring to prepare the garden knowing that my operation would put me out of action for a while.

Viv's garden

Looking from the sofa my eyes encounter the patio first, which is packed with pots of pelargoniums, lilies, geraniums, dahlias, fuchsias and a huge hanging basket overflowing with lemon -scented begonias. As I write I lament the denuding of our lemon tree outside the window, which bore 18 ripe, juicy lemons in early summer. I can’t complain, however, as my husband and I have enjoyed the fruits of its bounty in the form of 36 gin and tonics on many warm summers evenings!!

Soft grey patio pavers slope down from the patio onto a small lawn, it’s curved edges lined, on every side, with colourful flower beds. Although I have been cursing the snails, which have been devouring most of the annuals that I grew in the spring, they have at least left abundant golden rudbeckia and fluffy blue ageratum which tumble merrily onto the lawn.

Viv's garden

It’s a real delight to take a morning stroll (or hobble) around the borders to discover what has come into flower each new day. I have been thrilled with my new Alstroemeria ‘Indian Summer ‘ that are in full bloom right now. Hugh and I were so impressed when we spotted them growing on Wisley’s trial beds, that I came home to order them that very evening.

Beyond the alstroemeria, Geranium ‘Rozanne’ never fails to impress with masses of rich blue flowers from June to October. They create an excellent foil for Rudbeckia and blue spires of Perovskia beyond.  I’m so proud to have grown 6 different colours of Phlox this year. My latest addition, called Phlox ‘Blue Paradise’ is an incredible purplish blue. It’s just  wonderful!

Viv's garden

Towering flame orange Tithonia (Mexican Sunflowers), Cosmos ‘Purity’, Helianthus ‘Lemon Queen’ and evening primrose all add excitement and height at the back of the borders. Fortunately each bed is so jam-packed that there is not much room for weeds!

The only problem is… it’s snail & slug heaven! I have been shocked to find that this year’s snails must be a super-breed with jaws strong enough to eat through the hairy tough stems of sunflowers( all of them!!)

A tantalising glimpse of a brick-paved area and vegetable patch can be seen through an arch beyond the lawn. Today Hugh re-potted his banana tree and it can now be seen waving it’s huge leaves behind the bird bath in the middle of the brick circle. I can just about glimpse the scarlet flowers on the runner bean canes in our miniature veg plot on the far side of the brick circle, reminding me to ask Hugh to keep picking the veg for dinner each day. The enormous cucumbers (‘Swing’ F1) have been a real surprise this year. I grew them up a vertical support for them just before going into hospital and so many have grown in a few weeks just from one plant in one pot!

Well, I could carry on like this for ever. I haven’t even mentioned my new shade border with 4 newly purchased, remarkable clematis. (the best has turned out to be one called ‘Pernille’) My enthusiasm for my garden never wanes! Unfortunately the same cannot be said of my stamina which is being curtailed by too many painkillers currently.

Although I could not join  you all in Charlton House garden for the first real live meeting since Covid struck, I will be thinking of you all and hoping that the evening goes well.

Recovery from my op can take months but I am determined to bounce back in record time so wish me luck. Anyway how could I fail to recover quickly when I can see the biggest incentive outside my window?

Viv

Supporting Plants

Supporting plants in a timely manner has been one of members’ New Year’s resolutions on more than one occasion. I remember one reading: to support plants before they fall over!

But how to do it in a way that is both attractive and unobtrusive? In addition to which, you have to find the right materials. I have long been an admirer of the ‘birch halos’ used by Sarah Raven and at Great Dixter, for example, but had never attempted to create one.

This year I managed to find myself a pile of birch twigs and, inspired by the clear instructions in Arthur Parkinson’s book The Flower Yard, I had a go.

As you can see from the Antirrhinums, although not quite on the same level of skill, my efforts  are doing the job and don’t look too bad!

I wonder what other attractive supports members have found for themselves?

Vija