Spring 2024

Clematis Comtesse de Bouchaud

The mauvy pink flowers of Clematis Comtesse de Bouchaud (often misspelled as Bouchard) are just so beautiful with their crepe georgette texture and are produced over a long time from late Spring to late Summer. Planted at the base of the hedge of Viburnum tinus behind the the North facing picket fence, gives it the ideal spot with its ‘roots in the shade and head in the Sun’.

If you don’t have a similar position you can keep clematis happy by using thick mulch to keep its roots cool and moist.

Confusingly I have seen this particular clematis classed as both a Group 2 and a Group 3 Clematis. Group 3 Clematis require hard pruning, by cutting back to a pair of large buds around 30cm from the ground in late Winter or early Spring. Group 2 Clematis are usually not pruned back in Winter, but just pruned back by half after the first flush of flowers. Being a combination of both 2 and 3 basically this means that you can prune the Comtesse as either or as both. You could hard prune all the stems except for a few and that would mean that you would get earlier flowers, and then also after the first flush prune her back about half way to encourage a second bloom.

Spring Jude the Obscure

Jude the Obscure

Rosa ‘Jude the Obscure’ and buds of Penstemon ‘Blackbird’

Spring roses and other garden delights.

Some snaps of the garden in mid Spring. This season has been dry and warmer than usual, and I have added dozens of new plants, so watering has been a big chore as they get established. The roses and coming into their first flush, along with foxgloves, oriental poppies, and lupins.

Oriental poppies and foxgloves

Old garden rose Madame Hardy. A once flowering Damask rose with perfectly formed rosettes with a green button eye and a sweet fragrance of honey. Exceptionally disease resistant and highly recommended.

David Austin rose ‘Shropshire Lad’ by the front door. This and other roses have been plagued by a wild looking caterpillar Chlenias auctaria, whose favourite food is evidently rosebuds.

Bearded irises

Rosa ‘Shropshire Lad’

Pink Russel lupins and white foxgloves.

Clematis ‘Gypsy Queen’ in her second year and really thriving on the front picket fence.

Rosa ‘Olivia Rose Austin’

Rosa ‘La Belle Sultane’ and Geranium ‘Rozanne’

Looking back at summer past

Spring has officially arrived, and as I am busy adding some new plants to the existing beds (and I have extended the western border) I am looking back at photos of the past Summer. There are gaps to fill and forms, colours and textures to harmonise.

Some perennials I am adding to the garden this year include: Verbascum chiaxii, Dowdeswell delphiniums, Euphorbia shillingii, Calamagrotis brachytricha, Stachys moneiri ‘Humello’ and so much more!

New roses I have added to the garden include: Ballerina, Rosa gallica ‘Officianalis’, Young Lycidas, Princess Anne, England’s Rose, Mary Rose, Gertrude Jekyll, Madame Isaac Pereire, Sombreuil, Teasing Georgia, Jaques Cartier and a hedge of Purple Rain.

I am busy growing things from seed including Echinacea purpurea and E. pallida. I am also planning on adding annuals such as cosmos and zinnia, to fill the gaps left by lupins and foxgloves etc.

It’s thrilling to look at so much bare ground, and perennials freshly cut back after their winter sleep, and know that in a matter of weeks the garden will be blooming again.

I can’t wait to see my roses again, and meet the newly planted ones for the first time.

Symphyotrichum (Aster) 'Little Carlow'

I planted five ‘Little Carlow’ Asters last Winter, but only two survived Basil the dog’s digging efforts. But those two plants have put on such a show. The correct name is actually Symphyotrichum 'Little Carlow', until recently it was placed in the far more pronounceable Aster family. It is a hybrid between Symphyotrichum cordifolius and novi-belgii, so perhaps the most correct name would be Symphyotrichum cordifolius x novi-belgii ‘Little Carlow’? They had grown very tall and were covered in hundreds of promising buds by the end of Summer, and it was so thrilling when they all opened and there was a sea of pretty mauve stars.

Next year I plan on doing the antipodean equivalent of the ‘Chelsea Chop’ (which is done in May in England) in late November, to keep the plants more compact so that they won’t require staking. The plants I had are too small to divide just yet but I just planted another six plants (purchased from Yellow House Perennials), so I am hopeful of another beautiful, and even more spectacular starry show next Autumn.

Roses and Perennials

Some exuberant combinations of perennials and roses in the island bed at the top of our garden this Summer.

Achillea ‘Blue Boa’ (it’s really purple not blue), R. Lady of Shalott, Lilies and Veronicastrum ‘Pink Glow' and R. Munstead Wood

R. Jude The Obscure and Salvia uliginosa

R. Munstead Wood and Veronicastrum ‘Pink Glow’

Rose Munstead Wood is a beautiful rich magenta here in the warmth of Summer and much darker and more crimson in early Spring and Autumn. I love the contrast of the voluptuous rosettes with the glowing spires of the Veronicastrums.

R. Munstead Wood, R. Lady of Shallot, Achillea ‘Blue Boa’ and also glimpses of Stachys byzantina

R. Jude the Obscure and Salvia uliginosa

Graft union, to bury or not to bury?

A perennial question - should you plant grafted roses, with the graft/bud union above or below the soil level?

The biggest Australian rose nurseries and many books advise you to plant roses with the bud union above the soil level, (for example Treloars planting advice here. ) However I have found in my own garden, the few roses that I have planted with the graft union above the soil are much more susceptible to windrock. The plants that have the graft union buried also have the best of both worlds- the rootstock to get them started quickly and then eventually they will send down roots from the scion, making for a stronger and more stable plant. I am told that eventually they will become ‘own root’ and this mean that the roses will hopefully have a longer lifespan. But don’t take my word for it, two pre-emminant rosarians Michael Marriot and Paul Zimmerman both concur that planting the graft union below the soil is the best way in all climates.

Desdemona David Austin Rose Review

Just a quick post to write how happy I am with my Desdemona rose, now in her second season. She is doing so well I have ordered a second.

I am really impressed by the amount of blooms she produces, and her excellent health in very trying wet conditions. She has such elegant white chalice shaped flowers delicately blushed pink that do not ball and are held quite upright. The leaves are also very handsome and the entire bush is well shaped.

I highly recommend this rose for similar conditions, as it is really thriving in my garden in the Blue Mountains Australia. I think like other English Roses, Desdemona responds well to deep waterings and the heavy spring rains ensured a tremendous amount of flowers in her Spring flush - just look at the number of buds in the fourth photo! The scent is fresh and citrusy and very pleasant though I didn’t find it that strong- perhaps that will come with a bit more time in the ground. Looking forward to seeing it look spectacular as it matures over the coming years, David Austin Roses often really started to show their brilliance in their fifth year.

Olivia Rose Austin Review

Three and half years ago, my husband and I planted the first roses in our garden. In mid winter by the time I was getting home from work at Everglades it was dark so we did it by torchlight. Among them were three Olivia Rose Austins. I remember deliberating for a long time about which rose to put in this particular spot, as it is visible from the kitchen window and in prime position framing the deck. I needed something really healthy, as it would be shaded until mid morning and then be blasted by afternoon sun, and also a rose that bloomed prolifically, and formed a shapely shrub

Anyway three years later I really couldn’t be happier with my three Olivias. They are exceptionally healthy - I have never seen her with any blackspot - truly miraculous! And she blooms her head off really. Although I gather she is quite drought tolerant I think she really enjoyed this very wet Winter and Spring.

Some plants for (temporarily) boggy spots

The last few years since January 2020 have been ones of almost continual rain here- and we are lucky that we are on the side of a hill and not in a flood plane, like so many that have been badly effected by floods. We knew when we moved in that there was a natural spring half way up the garden (the land used to be called ‘Spring Hill’) but nothing quite prepared me for the mud and muck and boggy soil that was to come. I think before this area of Blackheath was cleared (and planted with orchards) our garden must have been a hanging swamp!

So a lot of things I planted in what was dry dust in 2019 (that we amended with truck loads of organic matter) haven’t survived - but I wanted to share some of the success and failures, in the areas of our back garden with the poorest drainage (there is a clay layer beneath the soil, and with all this constant rain there are sections that stay completely waterlogged and deprived of oxygen). When I realised how boggy it was getting I removed the dying Salvias, Penstemons, Echinops, Campanula, Cistus etc. and replaced them with some plants that do not resent having such wet feet.

Successes:

My roses seemed to be soldiering on, and look really very healthy, despite some balling badly (R. ‘Earth Angel’) in the constant heavy rain.

Filipendula rubra - also known as Queen of the Prairie. I chose this spectacular plant because its natural habitat is apparently ‘calcareous fens’ - which are rare peat wetlands fed by underground springs that pass through calcium rich rock such as limestone, unsurprisingly it is thriving, (albeit with the addition of lime- as my soil is very acidic). Hopefully it won’t take over the whole plot!

Alchemilla mollis - seems to love it.

Viburnum opulus ‘Sterile’. - I saw the guelder rose on a list for wet soils and it is really thriving- have planted some more.

Lythrum virgatum ‘Rose Queen’ - as a wetland weed, I figured the loosestrife would be able to cope. And so it has. I have also read it it a bit of a thug so I am careful to cut off flowers before they turn to seed.

The Veronicastrum virginicum ‘Pink Glow’ I planted also seems very healthy. The Echinacea I planted in front of it (such a pretty combination) is not as happy as I thought it would be, but I am going to persevere as perhaps the summer will hopefully be a bit dryer? We can only hope.

I have recently planted some Iris siberica ‘ Pink Haze’ which seems to be doing very well. Siberian Iris, like the Japanese Iris (or Iris ensata) can cope with flooded soils.

Some things I have recently put in light shade and it’s too early to tell yet - Astrantia major , Aquilegia cvs., Astilbe, Convallaria majallis (Lily of the Valley), Polygonatum (Solomon’s seal).

Some thing I noticed is that things that are thriving: Filipendula, Alchemilla, Sanguisorba and the wild strawberries that are trying to take over, and of course the Roses are all in the Rosaceae family. I think Geums would also do well, but I haven’t found a way to incorporate their hot colours in my garden of pinks and lavenders. Aruncus (Goat’s Beard) is another plant in the Rosaceae family that would also be happy in a bog. Perhaps Potentilla would also be content.

I was growing Salvia uliginosa - but it was doing so well I had to take it out. It really likes to spread very quickly through wet soils. It is so pretty, with azure blue flowers, perhaps when other things are more established I can risk putting it back in?

Other plants that I have considered but haven’t added (yet?) are Rodgersia, Gunnera manicata, Ligularia, Lysimachia clethroides, Angelica, Calla Lilies and Hemerocallis (daylilies). I rockon Cranberries would do very well too.

When reading the planting notes for a lot of these plants- I noticed that a lot of them mentioned that once established they are more tolerant of dryer soils, so hopefully by the time we get a dry summer again these plants will be tough and resilient! Fingers crossed.

Anyway I hope this small list of plants for poorer draining spots will be useful to someone else struggling with similar conditions as me. May we have a bit more sunshine this Spring and Summer on Australia’s East coast.

Garden update photo dump

Things surviving this incredibly wet season

Soil pH and Roses

Plants are adapted to different environments that foster different soil pH values - think of the oak-health woodlands of North America with Rhododendron, Kalmia and blueberries (Vaccinium) versus the parched calcareous cliffs of the mediteranean with Lavandula dentata. Plants also need nutrients and minerals in different ratios and the right pH allows for the uptake of adequate nutrients which become unavailable outside their ideal range.

The chart below is from the NSW Department of Primary Industries.

Influence of pH on Nutrient Availability

Roses like neutral to slightly acidic soil with a pH between 6 and 7

As you can see in the chart above most nutrients become less available as the soil gets more and more acidic - except for Iron. For instance potassium (K)- a nutrient very important for strong healthy cell walls becomes less available as pH drops below 6. This means that plants will be more susceptible to fungal diseases such as blackspot. Likewise if your soil is above 7 the availability of iron, copper, zinc and manganese starts to wane.

If roses are unhappy with your soil pH they will show with unhealthy leaves and lack of vigour. For instance a too alkaline soil might lead to interveinal chlorosis caused by iron deficiency. If you suspect this, testing the soil pH around the rose would be a good first step.

Also in some rose forums I have seen it mentioned that specific roses respond to different pH soil with slightly different colouration and also stronger or weaker scent. So if your rose was promised to be fragrant and is lacking scent, it might be worth testing you soil pH too. Most nurseries sell easy to use pH kits - I like to use this one developed by the CSIRO.

Ideally you will not have to try to modify your soil pH. I think the less interventions in your native soil and growing suitable plants is best. But if you want to grow vegetable crops or exotic ornamentals like roses and your soil pH is slightly out of the optimal range you can nudge it towards what you want with amendments.

In some parts of our garden we have suuuper acidic soil, with a pH of 4.5. I have amended the soil (at various times, not all at once) with garden lime, wood ashes (from our fire place) and home made compost, and heaps and heaps of mushroom compost and the pH is now closer to 6. We had 3 cubic meters of mushroom compost and 1 cubic meter of cow manure delivered by a local supplier Tunks . This is what that looks like:

I tested the mushroom compost and it has a pH of 8 (alkaline) I will have to keep monitoring the pH.

Hopefully you have the perfect soil, but if you are going to add lime to your soil because it is too acidic be aware that your soil texture will determine how much lime you need to add to shift the pH - as sandy soil is much easier to shift than clay you need much less. Lime and dolomite products differ so I am not going to recommend dosages - you need to follow the directions on the packet. Over applying lime can lead to other nutritional deficiencies as it puts other ratios out of balance and so it is better to apply only a little a time and wait and observe in between applications. Changing pH is a slow process!

If you have very alkaline soil you could try using leaf mould, spent coffee grounds and chicken manure and acidic mulches such as leaves and pine needles to help lower your pH. You can also use sulfur or iron sulfate.

NB: Before adding any amendments (or buying large quantities) I think it is important to first test their pH. Cow manure, for instance, is generally thought of to be an acidic to neutral soil ammendment, (and therefore often advised as a suitable amendment for roses and camellias) however I think it must differ a lot according to source and the cows’ diet. I tested three different local supplies of cow manure at a pH 8, and a bagged cow manure from my hardware store was also pH 8.

Some Soil Ammendments

ACIDIC

Pine needles

Leaf mould

Pine bark mulch

Coffee grounds, Spent tea leaves

Compost (without added lime)

Fowl Manure (more acidic) and possibly some Cow manure (without added lime)

Sphagnum peat

Elemental Sulfur

Iron Sulfate (Also called Ferric Sulfate)

Specialist Camellia fertiliser

ALKALINE

Wood ash

Stabled horse manure (lime added)

Mushroom compost

Garden Lime

Dolomite

Some cow manures

Jude the Obscure

This little cluster of roses almost looks like three fluttering fat cherubs to me. The roses never open fully and so remain perfect orbs of pale apricot.

And the smell? Powerful and intoxicating - like lychees and sweet white wine.

Despite her delicate and demure appearance she is real tough - battling through our heat wave, drought and bush fires and consistently pumping out blooms and looking really healthy. She seems to like it hot and is coping with being next the house and getting a blast of hot afternoon sun too. Also her flowers are held upright on strong stems despite their size. I do try to give her at least 10 liters of water once a week when we haven’t had much rain. She has had compost and Sudden Impact and now some more mushroom compost.

This is a rose I would highly recommend to anyone with hot summers and I think it would do well in Sydney too. Just put her somewhere where you can enjoy her fragrance.

The only thing I can fault Jude for is her blooms do shatter quickly and so she is not such a great rose for a bouquet but still worth picking to be on the bedside table for a few nights.

And I love her so much I have bought three more!

Update:

My Judes are growing from strength to strength, and getting quite large and providing armfuls of flowers for the house. A very special rose that does very well in the Blue Mountains.

Selecting Roses for Blue Mountain's Gardens

If you like me, have been beguiled by all the frothy images of David Austin and old garden roses, you may be wondering if they will do well in the Blue Mountains. The answer is a resounding yes! However the key to armfuls of roses and healthy bushes is understanding your garden’s climate, soil and light patterns and selecting suitable roses and positioning them well.

So as a budding rose enthusiast I want to share some of the insights that I have gleaned through the writings of experienced rosarians and also from my experience choosing and growing roses in the upper Blue Mountains.

Things to consider when choosing roses:

Sunlight

Roses require full sun, which means at least 6 hours of sun per day. However I find some roses do not cope with hot afternoon sun, so a position that gets morning sun is ideal. Also as dew will evaporate quickly, morning sun will help prevent blackspot and other fungal infections. Doing a sun chart of map of your garden often reveals surprising results, with areas considered full shade possibly having more sun than previously thought and vice versa. The best way to do it is at various times of the year (say Spring and Mid Summer especially) put major areas of your garden on a chart and record whether they are in Sun, Part Sun or Shade at each hour of the day. This may seem like a time consuming exercise (you could do the same by setting up a time lapse camera) but will be invaluable for understanding your garden and possibly squeezing in more roses.

Although roses like full sun, some cultivars can do very well with a little bit less, and they will also perhaps hold on to their colour and scent a little longer. Roses in shade may grows bit taller, so you might need to prune a little bit more to keep them compact.

Roses that cope with partial shade (4-5 hours of sun per day):

The most shade tolerant: Rosa gallica ‘Officianalis’, Rugosa roses, Celeste, Cornelia, Ballerina, Iceberg

English Roses: Olivia Rose Austin, Roald Dahl, Princess Anne, Shropshire Lad, Lady of Shalott, Heritage, Abraham Darby

Climbers: New Dawn, Sombreuil, Zephirine Drouhin, Climbing Cécile Brünner

Sally Holmes, Cecile Brunner, The Fairy, Blueberry Hill, Bonica, Lavender Lassie, Complicata

High Rainfall

If you are in a high rainfall area and have rainy humid summers, like in Blackheath, choosing roses that don’t ‘ball’ (where petals in an opening bud stick together and the flower fails to open and rots) would be wise to avoid disappointment. I have found that deeply cupped roses with a very high petal count (those luscious cabbage-like roses) and thin petals are more likely to ball such a Souvenir de la Malmaison and some Kordes roses such as Earth Angel and Jasmina. I actually ended up removing my Climbing Souvenir de la Malmaison, despite the breathtaking beauty of her flowers, because the blooms were just too scarce and all but a few balled terribly. My Olivia Rose Austins do ball sometimes, however they produce roses so prolifically that I can just snip off the offending blooms and still have a good show.

Some of the rare roses of Souvenir de la Malmaison to actually open.

Some rain resistant beauties:

Single or semi double roses are a better choice than incredibly full roses. Examples: Nevada, or the stunning rugosa Roserie de l’Hay

English Roses that won’t ball: Princess Anne, England’s Rose, Desdemona, Tottering by Gently. Gertrude Jekyll is also supposed to be rain tolerant (it is my first year growing her, I will report back!)

David Austin Rose Desdemona

Soil

Roses are pretty tough and adaptable. But ideal conditions are a pH around 6.5, and soil on the heavier side, while still being well drained. This is because roses are hungry and thirsty plants and soils with some clay are better at holding moisture and nutrients (clay has increased cation exchange capacity) than very light sandy soils. The exception to this is Rugosa roses which actually prefer sandier soils, although they will tolerate clay as long as it is well drained. If you have either heavy clay or sandy soil amending your soil with organics such as compost, leaf mould and well rotted manure will improve drainage and also moisture retention.

Roses for Sandy Soil

Rugosas

Gallica roses such as : Charles de Mills, Rosa gallica ‘Officianalis’

Wild species roses.

David Austin also lists Claire Austin, Olivia Rose Austin and Lady of Shalott as ideal for poor soils.

Disease Resistance

High disease resistance (blackspot, rust, powdery mildew) should be at the top of your list of required traits if your garden gets misty or humid, especially if you don’t want to spray. A little bit of blackspot is nothing to worry about and usually can’t be avoided, however disposing of fallen leaves and mulching the ground thickly can help keep it at bay.

Kordes roses are exceptionally healthy!

Rugosas again are very disease resistant. Also remember never to spray the leaves of Rugosas with anything as they resent it.

David Austins with fantastic disease resistance: Olivia Rose Austin (completely blackspot free for me, even with no morning sun!) Munstead Wood, Claire Austin, Princess Anne. In my garden I have found that Wollorton Old Hall and Shropshire Lad get the most blackspot, although it doesn’t seem to effect the amount of flowers. I do feel that is it really important that climbers remain healthy as their leaves can’t hide behind other shrubs.

Brindabella Roses are bred for Queensland conditions and have a line of roses specifically bred for black spot resistance. I haven’t tried any yet but have my eye on a few! They would definitely be worth a try, especially in the lower blue mountains as I imagine they would cope with summer heat very well.

NB: If you do spray for fungus, make sure you use something organic such as Eco-organic eco-fungicide which is just potassium bicarbonate, as fungicide are some of the most toxic garden chemicals. You can make up a spray with some potassium bicarbonate, horticultural oil (eco-oil) (so that it sticks on the leaves), seaweed powder, and some liquid sudden impact or Charlie carp to give a foliar feed at the same time as you spray (using dosages recommended on packaging). Spraying foliage with just a solution of the Eco-organic seaweed powder is also a great preventative as it very high in potassium which is important for strengthening cell walls and resilience to foliar diseases.

Hardiness Zone

Hardiness in the Blue Mountains is generally not a problem for most roses as we just do not get cold enough to bother them. However you may be in a particularly frosty area or microclimate, and I would recommend avoiding doing your major pruning until at least early August .

Here in Blackheath, the average annual lowest temperature is -3.6°C, and this corresponds to a USDA hardiness zone of 9.

USDA ZONES

Using average lowest annual temperature.

You can find out similar data for your area using BOM’s climate data. Select monthly lowest temperature, then enter your location and choose the closest station and click get data. Scroll down and look under Summary Statistics for All Years. The lowest annual temperature is what you can use to find what USDA zone your area corresponds too. This USDA zone number is very useful when using sites like helpmefind.com, which will say things like “USDA zone 5b through 10b”.

Some roses (especially some old garden roses and species roses) need vernalisation or winter chill hours to flower well (just like some fruit trees like apples do) so that is also something to check if you have mild winters and are in a USDA zone of 10 or above.

Some areas in your garden may be hotter (heat reflecting off walls or paving for instance), frostier, or dryer (under eaves, near established trees, or next to walls). Observe you garden carefully. Keep this things in mind when positioning your rose.

Drought and Heat tolerance

Hybrid Teas in general need quite a bit of water to thrive and keep on blooming, in contrast once blooming old garden roses are likely to need less water to put out their annual show.

David Austin roses are notoriously thirsty! It makes sense as a lot of England has high rainfall. However there are cultivars that are better than others. Roses that are reputed to be drought tolerant will also cope better on sandy soils that dry out quickly.

Obviously you can do a lot to help your roses through drought - drip irrigation, deep mulching, compost amendments, soil wetter if you soil gets hydrophobic. Also avoiding very hot sites and areas exposed to hot midday and early afternoon sun will help when temperatures climb. If a very hot summer is predicted, it may be advisable to give your roses a prune instead of a deadhead after the first Spring flush. This will delay flowering, hopefully until after the hottest parts of Summer are over and save losing roses to crisping in a heatwave.

Rugosa roses and rugosa hybrids are drought tolerant and like sandy soils.

Roses with China heritage such as Mutabilis are also supposed to cope with not much extra water once established.

Tea roses (not hybrid teas) are said to be drought tolerant once established. Such as the classics Duchesse de Brabant (aka Comtesse de Labarthe)

Ramblers are generally pretty deep rooted and drought tolerant.

Mrs. B. R. Cant is reputably a very drought and heat tolerant and will also do well in Sydney.

Gangly giants and house Eaters

What might be a demure and well behaved shrub in Shropshire may become an octopus-tentacled monster with our hot summers.

Assume that many English Bred roses will exceed their size description. Some English Roses that stay compact:

Tamora (an apricot coloured rose with a Myrhh fragrance), Munstead Wood, Darcey Bussel, Boscobel, Ambridge Rose, Princess Anne

Ross Roses have actually tried to breed English Style roses that remain compact in Australian conditions- such as Lady Phelia, which is a compact version of Abraham Darby.

Beware Gales

Many areas in the Blue Mountains are really windy.

Don’t plant rose standards (roses grafted onto long stems) in high wind areas. Also smaller compact shrubs will withstand winds better than tall bean stalks (think of plants adapted to high wind areas like heathers) so if you have a windy spot pruning your roses so that they stay compact will reduce damage. Also some roses have more delicate foliage than others which is something to look out for if your garden experiences a lot of wind - delicate leaves will end up looking tattered quickly. Alba and Rugosa roses, have tough foliage and cope with exposed positions well.