The White Glossary


‘The White Glossary’

For the curious and hungry-for-knowledge, the glossary is stuffed with things you need to know to become a gardener. We make a point to weave, thread and insinuate horticultural, meteorological, botanical, geological and evolutionary knowledge through everything we say, write and do. For us this is as much an essential professional horticultural discipline as it is an all consuming analytical and inquisitive practical obsession. We don’t just want to grow gorgeous, shapely plants – we want to teach as well and as a result, maybe encourage you to do something different and new in your garden. Some terms are our own – arrived at in the absence of existing terms to describe some of our innovations and practices. Many are pertinent for the job in hand but don’t hold us to task for omissions – we are not done yet.

Index :

1.Biological Control… 2.Blob… 3.Botanical Latin… 4.Broad genetic base… 5.Broad leafed… 6.Built-up Coastal… 7.Climate and Microclimate… 8.Cloud Pruned… 9.Co-dependent… 10.Coniferous… 11.Conservatory Plants… 12.Coppice… 13.Creative Maintenance… 14.Crown raised or lifted… 15.Deciduous… 16.Dicot… 17.Drought tolerant… 18.Endemic… 19.Epicormic growth… 20.Epiphyte / Epiphytic… 21.Evergreen… 22.Fastigiate… 23.Feathered… 24.Frost Pocket… 25.Genus… 26.Glaucous… 27.Gherkin… 28.Habit… 29.Hardy… 30.Haircut… 31.Half Standard… 32.Hedge… 33.Indoor/House Plants… 34.Indumentum… 35.Karikomi… 36.Microclimate… 37.Micropropagation… 38.Monocot… 39.Mound… 40.Multi stemmed… 41.Niwaki… 42.Pathogen… 43.Pests and Diseases… 44.Posh… 45.Pot Plants…46.Provenance… 47.Relic… 48.Shrub… 49.Species… 50.Standard…51.Suckers… 52.Taxonomy… 53.Tender… 54.Topiary… 55.Tree… 56.Tropism… 57.Twmp…58.Urban Heat Island… 59.Wrapping for Winter

I’m not an expert on Botanical Latin so I proceed with caution but Latin names often help by describing the leaf or flower. There’s not a huge vocabulary used so it’s not that difficult but here are a few examples : we grow a tree called Lyonothamnus floribundus aspenifolia. Not sure about Lyonothamnus (probably named after someone called Lyon as in Corner House), ‘floribundus‘ means ‘flowers a lot’ and ‘asplenifolius‘ means it has a ‘leaf’ (‘folius‘) like a ‘fern’ (‘aspleni-‘ refers to the Asplenium fern). Another good one is Hebe parvilflora angustifolia. Hebe means it’s a Hebe (Greek Goddess?), ‘parviflora‘ means ‘small flowers’ (‘parvi‘ – ‘small’, ‘flora‘ – ‘flowers’) and ‘angustifolia‘ means narrow leaf (‘angusti‘ – ‘narrow, ‘folia‘ – ‘leaves’). “Can I have a Hebe parvilflora angustifolia?” might be a mouthful but it’s got to be better than “Can I have ‘The Plant (possibly) named after a Greek Goddess with small flowers and narrow leaves? please, thank you very much”. We have a book in our library called ‘Botanical Latin’ that may or may not get put on your present list but here, I hope, I have given a taste of the subject and its importance. Three cheers for the Taxonomists – wherever they are. No idea. Gary Larson cartoons come to mind.

An example of climate would be to describe the British Isles as having a ‘cool temperate maritime’ climate. Cool because we lie far north – between 50 and 60 degrees north of the equator, temperate because we never get very hot or very cold conditions and maritime because we’re surrounded by sea which is remarkably stable in temperature in all seasons and its influence is to warm us in winter and cool us in summer. This influence is exaggerated by the fact that weather systems in the northern hemisphere tend to move from west to east – thus often introducing warmer air from the north Atlantic (the Gulf Stream) into the British Isles. West facing coasts in the northern hemisphere (Oregon, Washington and British Columbia) benefit from warmer air from the north Pacific as do the British Isles, France and Norway in the north Atlantic. The eastern coastal states of America (on the shores of the eastern north Atlantic) and Korea and Japan (on the eastern coast of the north Pacific) do not benefit significantly from the moderating effect of the sea because their air is coming from the land; colder in the winter and hotter in the summer.

Microclimate is affected by topography, the proximity of the sea and large urban areas. Probably the finest example is London. One of the largest urban conurbations in the world, it has a dramatic effect on minimum temperatures. Meteorologists call it the Urban Heat Island Effect. On a cold clear night in mid winter the temperature will drop as the sun sets and in rural areas it will often just keep dropping but in a large built up area the combined absorbed heat of miles of roads and millions of cubic metres of masonry will prevent the temperature dropping anything like as far as in the country. Other examples are : 1.The effect of being near the sea – the closer you live the more the warming effect and 2. Elevation. Cold air is denser than warm air and runs down hill. If it runs into a valley without a large exit (known as a frost pocket or frost hollow) the cold air collects and the temperature can keep dropping all night until the sun rises and warms the air. These differences bought about by the factors described above are not trivial. On one occasion we measured the temperature in a small back garden in Notting Hill, London at -4c and at our old nursery In a frost pocket in West Sussex 40 miles away it was -17c.

Climate and microclimate are huge subjects and the two paragraphs above hardly scratch the surface but you’ll never become a gardener unless you have at least an inkling of how our weather systems work.

To start with it was difficult. We tried to dispense good and useful advice but we were a bit of a lone voice and probably sounded negative. We could hardly deny such accusations. Slowly, the truth dawned, the demand subsided and now, nearly 30 years later, the subject rarely even gets mentioned. If it does, we’ll suggest learning about biological control and using some of the plants we’ve learned are best adapted to the less than ideal conditions found in the average conservatory. Under ‘Plants’ on the menu on the home page there are lots of categories – including suggested plants for conservatories.

Trying to grow a plant in a pot is hard enough. Stick it in a hot dry building and it gets worse. By about 2005, heating greenhouses had become officially looney so we immediately dropped some of the more exotic plants we used to do for conservatories (despite their lack of suitability) such as Daturas, Tibouchinas and Bougainvillias. This meant the remaining choice was more frost hardy and one of useful ideas is – try it in the conservatory and it hates it, at least you’ll be able to bung it in the garden. Also, just giving a plant a spell outside for the summer could relieve the stress. Plants that would survive with little water (Cacti or Agave) or plants that lived in water (Papyrus) were always the top of the list because they weren’t going to suffer from the kind of capricious watering afforded by most human beings.

Also, biological control (essential) and good husbandry were recommended. It was all at variance with what the adverts for conservatories implied.

One of the most rewarding experiences is when we’re in a customer’s garden and we’ve just turned some boring shapeless old Portuguese Laurel into a sculptural and distinguished piece of topiary in 40 minutes flat. The excitement, the realisation, the enjoyment, the enthusiasm is a wonder to behold. The falling of the scales from their eyes, an epiphany, a Damascene experience. The predatory look in their eye as they look around the garden thinking “Hmmmm… what can we do next?”

Almost the first thing we ask our customers is “Where do you live?” One of the many reasons is to establish the topography – are you on a hill (more wind, less frost) or down in a valley (less wind more frost)? It doesn’t necessarily have much bearing on what you can and can’t grow but it does have a bearing on how some plants will react. Any plant that has the specific name ‘Japonica‘ comes from Japan and will probably start producing new growth as soon as we get one warm day at the beginning of March (it thinks it’s spring, we know it isn’t). If your garden is a frost pocket, the chances are that the new growth will get frosted, go black and have to start all over again. This isn’t a problem although it’s sometimes a bit disappointing – it’ll just grow again. If you’re higher, where the cold air drains away to be replaced by slightly warmer air, the new growth will be unaffected. We’d rather warn a customer that this could happen. Forewarned is forearmed and all that.

Two of the most famous frost pockets in Britain are Rickmansworth in Hertfordshire and Benson in Oxfordshire – the latter often mentioned in weather forecasts as being the “lowest temperature recorded last night“. Also, you’ll notice that weather forecasts often speculate on the lowest temperatures expected in “sheltered glens”in Scotland. All frost pockets. One of the most obscure studies from the H.M.S.O. (Met. Office) was a study done in the 1950s of a garden in Whyteleafe in Surrey. It seems that its altitude, the fact it was north facing (on the North Downs) and the soil was chalky (well drained soil radiates heat faster than soggy old clay soil and therefore gets colder faster) lead to there being no month of the year that you could guarantee that it was frost free.

The reference to well drained soil above is significant. Another well known frost pocket is Bournemouth Airport. Only four miles from the sea (where you’d expect it to be mild), lying in a bit of a depression (as airports often are) and on very sandy soil. The sandy soil gives up its heat stored during the day very quickly (much quicker than on heavy old clay soil) and the combination of these factors makes this spot on the Dorset coast, so prone to frost that it’s often mentioned on weather forecasts as recording the lowest temperature in the south of England on a particular night.

If you’ve got this far you’re a climate enthusiast so here’s another good one : one of the rather intense publications I used to get from the Met Office when it was at Bracknell was a record of an infra-red thermal aerial image taken above the intersection of the M23 and the M25 in Surrey on a particularly still and clear night in February. The image suggested that the temperature at the lowest spot on the M25 was -4c. Within about 2 miles at an altitude of 700ft on top of the North Downs, it was estimated that the temperature was +8c. An astonishing difference of 12c.

Bearing in mind the important understanding that there’s no such thing as an Indoor/House Plant (or Conservatory Plant, or Pot Plant or Wall Shrub for that matter), much can be learnt by observing the behaviour of plants indoors. Some might respond to electric lights nearby (the wavelength of light used by plants is little understood), some might enjoy a spell outside from time to time, some will do better by a window, all might get bugs (see Pests and Diseases on this page), all will benefit from having their leaves dusted and all need a saucer to sit in to stop the floor getting wet.

Like most establishments, the House Plant Industry is conservative. Understandably, they stick with what they know but experience has shown us that there are huge numbers of plants worth trying and occasionally one is genuinely surprised at what works and what doesn’t. The plants we list in this category have all been tried with conditional (obviously) success. There are more possibilities than Swiss Cheese Plants, Rubber Plants, Ficus benjamina and Poinsettias.

Pests in the nursery and in greenhouses and conservatories can be a problem and must be addressed either using Biological Control (good bugs that destroy bad bugs) or insecticides but how often do we use insecticides in the garden? Never is not an exaggeration. Never. We might use fungicides (for Box Blight for example) but bugs in the garden come and go and the garden is full of its own biological control (the balance of nature). If you get a really bad infestation of aphids on the young growth of plants in early summer, you could remove the young growth and burn it but really, the occasional epidemic is inevitable and is part of being a gardener. You might have a bad attack of something this year but you’re unlikely to get it again next year. Nature takes care of its own – as long as we don’t come along and screw it all up.

If you suspect you have a real problem, get in touch and send pictures. We will try to phone you (rather than play email ping pong) and ask forensic questions. You have been warned! For Biological Control, see 1. on this page.

There’s a nice little phenomenon that’s associated with the effect on plant populations of expanding ice caps : the orientation of obstructions to plant migration. Consider the Alps and Pyrenees. Both mountain ranges lie east to west and would have been a huge impediment to the southerly migration of plants which would have caused many to be wiped out. Now consider the orientation of the Andes and the Rockies – north south. Particularly in Chile and Argentina, there are many plants that – as a result of their unimpeded migration both up and down the Andean valleys – now have a geographical distribution thousands of miles of latitude. This means you can get the same plant as far north as Southern Peru and as far south as Southern Patagonia – an extraordinary 2500 miles. In our experience though, this can effect the hardiness of a single species according to their provenance; an example of the tree Maytenus boaria from Southern Patagonia could be very much more resistant to frost than one from Southern Peru. You can therefore understand that when we’re searching for material for propagation of plants to be grown in Britain, we’re always looking for plants from the coldest places – from the highest altitude and / or from the furthest north in the Northern Hemisphere and the furthest south in the Southern Hemisphere. And so it goes on…

Not surprisingly, most plant roots are positively phototropic and most plant branches are positively phototropic. Some plants are more positively phototropic than others which has a bearing on how you position them. Plant a Pine, a Maiten or a Eucalyptus next to a wood and they will grow towards the light so enthusiastically that they’ll bisect the angle between the wood and the ground – growing at 45 degrees.

Cold nights in winter come when the sky is clear and there’s no wind. If you’re in London on a night like that, you can feel the temperature dropping and then – nearly always just above freezing – the temperature stops dropping. The effect of stored heat in millions of cubic metres of brick, stone, concrete and tarmac, aided by thousands of boilers and millions of human beings. Out in the country, at the same time, the temperature just keeps falling and falling. The coldest temperature recorded in Sussex over the last 25 years was in February 1991. We recorded at the old nursery in Nuthurst -17c. The same night in the tiny back garden of a friend’s house in Notting Hill Gate, we recorded -4c. These are not proper screen temperatures that would be recognised by the Met Office but they were still correct and our interest is in relation to plants and where they will thrive and survive and where they will not. A temperature difference like that immediately explains the existence of those huge Canary Island Date Palm (Phoenix canariensis) on Kensington High Street, Orange Trees in roof gardens down the Goldhawk Road and various discarded sub-tropical house plants that have survived quite happily outside in SW1. Avacados, Yuccas from Guatemala, Kentia Palms and Ficus benjamina. We always say to our customers that you can grow almost anything if your phone number begins with 0207. We call it 0207 Land.

When I started the nursery – hungry for information – I got in touch with the Met Office at their old HQ in Bracknell. They were wonderfully helpful and kept bombarding me with HMSO official leaflets and studies on climate and microclimate during the 20th century. One was a study done in 1953 where a Landrover equipped with highly sophisticated temperature measuring equipment, drove on a clear, cloudless, still winter’s night from Epping in Essex to Weybridge in Surrey in a straight line through the City of London to measure the temperature gradient. It confirmed what everyone knew already – the nearer the centre of London (and any other built up area) you get, the warmer it gets.

One of the few times I was excited about getting a new car was when I bought one with a temperature gauge. They all have them now but in the 1980s, this was very unusual. Recently I bought a car with Sat Nav.I don’t have the faintest idea how to use it but I put it on sometimes because – miraculously – it gives you your altitude. The combination of knowing the temperature outside, and your altitude and observing the effect on temperature of altitude and the amount of buildings around you, turns your car into less of a means of transport and more of a mobile meteorological station. Heaven!

In Japan they have a tradition of wrapping some tree trunks and Cycads for the winter using rice straw in some of the colder parts of the country. It’s often a work of art that will have taken several people several days but it works and it looks beautiful.

In this country there are similar traditions but they tend to surround edibles rather than exotics e.g. figs had bracken tucked round them and pineapples were grown in heated glass frames.

The art of wrapping exotics to get them through winters that they were never designed to get through is in its infancy. We’re often asked how to wrap plants for the winter as if there are established rules surrounding the subject. Sadly, there aren’t. It’s mostly down to your own ingenuity, your desire to do it and a knowledge of the plant

Having said that, here are some ideas and observations from our own experience :

First :wrap according to the weather forecast and not the calendar. Some winters are so mild, wrapping is not necessary. If the forecast is for very cold weather, get out there and start wrapping. You’ve got to be a bit of a meteorologist to do this but that’s all part of the fun of becoming a gardener.

Second : don’t leave plants wrapped upfor too long – it’ll do more harm than good. Wrap up a Cordyline in October and unwrap it in April and it will be a dead and smelly mess. Just do it when it’s about to get cold and unwrap it as soon as the cold is over.

Third : use natural materials where possible – they allow some ventilation. Straw and hessian sheets are best and horticultural fleece is good but avoid plastic as it will just cause the poor thing to rot due to lack of ventilation.

Some specifics:

Dicksonia antarctica : There’s no point tying up the fronds as they always look so tatty when you unwrap them so cut the fronds off and wrap the trunk in layers and layers of hessian or fleece. Some people say they’ll benefit from having straw in their crown. I find it all very inconclusive because it’s clear that the frost hardiness of this plant varies enormously. One thing that does work is to build a stack of straw bales round each plant. We actually used to do that at the old nursery but that part of the garden ended up looking like a farm yard for three months every year and can you still get small straw bales anyway?

Musa basjoo : this is worth doing just to preserve the trunk and using the straw bales undoubtedly works. Cut the leaves off once the frost has got them and protect the trunk by whatever means you have at your disposal. A very cold winter will cause the trunk to collapse so protecting the trunk is worthwhile.

Cordyline : tie the leaves up if you can reach them. The old leaves will go some way to protect the tender growing points. Sticky tape works well

Phoenix canariensis : gaffer tape’s the only thing strong enough to hold it all together. Once it’s in a column of leaves, try wrapping in layers of fleece and more gaffer tape. An ugly white column. You can buy rush matting quite cheaply. Applying this round the fleece provides an aesthetic advantage.

Smaller herbaceous tender exotics in cold gardens : Echiums, Geranium madarenseMelianthus etc. : You can construct a little tent over them using sticks and fleece but it will only give minimal protection unless you introduce a heat source like an old light bulb (new light bulbs are so darned efficient they hardly give out any heat. What is the world coming to?). Alternatively, keep them in big pots, drag under cover in winter, or move to Penzance, Paddington or Puerto Rico.