Plant Collector: Lachenalia aloides quadricolor

The first lachenalia of the season: L. aloides quadricolor

The first lachenalia of the season: L. aloides quadricolor

The first of our lachenalias has come into bloom. ‘Quadricolor’ refers to the four colours in the blooms of this particular variety – lime green tubes with maroon tips are attached to the stem by a cap of orange and yellow. The commonest lachenalia that is seen in New Zealand is the somewhat garish, strong growing scarlet and orange which looks to me as if it should be sold amongst the plastic flowers in the red sheds. It is not in bloom yet. It used to be sold as ‘Pearsonii’ but that is an incorrect name, peculiar to this country. It is just a different form of L. aloides which is a variable species. We also grow L. aloides tricolor which is much later flowering and lime green with pale yellow and orange and the very different L. aloides var vanzyliae which is a striking pale blue and white with green tips.

Lachenalias are native to South Africa, predominantly the Cape Province. Most are winter flowering and summer dormant. We have different varieties flowering from now until early November in the garden. Many are easy enough to grow in sunny positions with good drainage, as long as you don’t get very heavy frosts. The foliage is not overpowering and doesn’t hang on too long after flowering finishes which makes for a tidier garden bulb. The highly desirable blue species come later in the season and not all are as easy to grow as L. aloides.

First published in the Waikato Times and reprinted here with their permission.

Garden lore: Friday June 28, 2013

Hooping roses to maximise flowering

Hooping roses to maximise flowering

Hooping roses to maximise flowering is a technique I first saw done in Ayrlies Garden when Neil Ross was head gardener. If you have a rose which puts out long, whippy growths, arching those growths over and tying them down hugely increases the number of flowers. This is because it encourages all the leaf buds along the length of the stem to set flower buds as well by dispersing the hormones which trigger flowering, rather than concentrating them at the top. I insert wire hoops and tie the runners down with stockinette. The ground cover plants will hide the wire hoops by spring time. It takes a bit of space – a metre or more on each aspect. In a narrow space, you can do it to either side only in a free form re-creation of espalier. It does work, I can vouch for that. The wire hoops are easy to relocate each season as required though I sometimes leave the long runners in place for more than one season, pruning back all the side growths.

I am pruning roses now, but those gardeners in more frosty conditions usually leave it later in the winter. Pruning encourages the rose into growth and that fresh growth is particularly vulnerable to getting burned by frost. Rake out all the fallen rose leaves while you are about it. These can harbour disease and, like spent brassicas, should not be put through the compost heap unless you make hot compost to kill off the nasties.

For more information, check out my earlier post: a short lesson in hooping.

First printed in the Waikato Times and reprinted here with their permission.

Know thine species

The show dahlia

The show dahlia

You can quite easily live out your gardening days without ever worrying about species and hybrids. Indeed you can, but as with most activities, many people will find that the more they know, the more they enjoy what they are doing.

At its simplest level, species are the natural form of a plant in the wild. And all plants originated somewhere in the wild.

Hybrids are mix of two different species in the first instance and after that they can quickly become a mix of many different species and resulting hybrids getting ever more complex genetic makeup. There is no value judgement in the rights and wrongs of that. Sometimes these hybrids occur in the wild without any human intervention (usually referred to as “natural hybrids”). Often it is done deliberately to try and improve plants.

A variation on controlled hybridising is line breeding – raising many seed from a plant and selecting only the very best with which to continue. Then seed from those best plants is raised time after time until it shows stability. Seed can be extremely variable and this form of line breeding is trying to edit out the less desirable aspects over several generations.

It happens all the time with edible crops. Think how much sweet corn and kiwifruit have changed over the years. The original, wild collected species of edible crops are often poor shadows of what we have now in terms of yield, reliable production, ease of handling and palatability.

It is not always true, of course. Sometimes commercial imperatives have seen us saddled with inferior tasting product – tomatoes are a prime example. And there are concerns about the loss of the wild species which are important to maintain the gene pool for food crops.

As far as ornamental plants are concerned, most of us will have gardens which are a mix of species and hybrids. There are no hard and fast rules although I have met a fair number of gardeners in my time who parade a collection of species only as a badge of status.

Species Camellia gauchowensis

Species Camellia gauchowensis

Some species have a simple charm which is lost in their showier hybrids. Others are nondescript in the extreme. Some highly desirable species are simply damn difficult to grow whereas the hybrids bring new vigour which makes them much more rewarding garden plants. Sometimes there are species which make splendid garden plants but they can be overlooked because their names are not appealing. Camellia gauchowensis has been the standout star of that family here recently and why anybody would grow the likes of Mine No Yuki instead of C. gauchowensis, I don’t know.

We have been revisiting the camellia species as we pick over the best options in the face of the devastating camellia petal blight which has so affected many of the hybrids we grow. It is not that the species don’t get it. It is just that some of them have less susceptibility and have other good characteristics which are worth looking at. More on this in the future.

Show blooms, no matter which plant family, often tend to be over-bred hybrids which are but distantly related to original species. Dahlias which are too heavy to hold their heads up without staking, bizarre daffodil forms, overblown cyclamen or chrysanthemums, enormous begonia flowers – anything that is bigger, allegedly better or a novelty genetic freak.

Named hybrid aster at top, self sown seedling at bottom

Named hybrid aster at top, self sown seedling at bottom

But controlled hybridising can also give us garden plants which are hugely better performers. You can see in the photograph of asters that the abundance of blooms at the top are from a named hybrid whereas the few poor specimens at the bottom are from a self sown seedling which has probably reverted closer to how the original species looks.

Hybrid arisaemas for our own garden

Hybrid arisaemas for our own garden

I am of course married to a plant breeder who is driven by the desire to create better performing garden plants. Sometimes it is just to get plants which will grow better in our garden here. His work with arisaemas is of this ilk. Many of the desirable arisaemas are a battle to grow in our conditions with insufficient chill and they simply don’t come back a second year. By hybridising two different species, he can get hybrid vigour which means they are much more reliable and stronger growing.

Other plants may be hybridised to look for new or improved characteristics – extending the colour range, reducing the impact of disease, getting more compact growth, better floral display, a longer season, sterility (to avoid unwanted seeding) or bringing the best features of different hybrids together in one plant. There are many reasons to hybridise and one of the final tests before selecting a new cultivar for release is to measure it against both the originating species and the actual parent plants. If it is not a significant improvement, then it won’t get released on the market.

Hybrids have their place in the ornamental garden and in the edible garden. But in a world which is squeezing the natural environment in every way possible, we need to retain the original species for reasons of ecology and bio-diversity. The more people who understand the difference the better – even more so if they can move away from the modern “green” cliché that says the original species are, by definition, better. They are not, but they are important.

First published in the Waikato Times and reprinted here with their permission.

Garden lore

“Now that all the other many-hued flowers have scattered without a trace, the dead white heads of the miscanthus remains alone in the fields until the end of winter. As it stands there so gracefully, not realising that it has entered its dotage, and bending its head as if in memory of past glories, it looks exactly like a very old person, and one cannot help feeling sorry for it.”

Sei Shonagon , The Pillow Book of Sei Shonagon (tenth century),
translated by Ivan Morris (1967)

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Pruning wisterias
Winter is the pruning time for many plants, but none more so than wisteria. The most common reason for their failure to flower in spring is savage pruning. Don’t cut them off at ground level because they flower from last year’s growth so you will be cutting off all the potential flower buds which form on the spurs. Think of them like an apple tree. Find the main stems which give the framework or shape to the plant. Shorten all the other whippy growths to between 3 or 4 leaf buds from the main stems. Thin out the ones at the base by cutting them back flush to the trunk. You don’t want the growths which sneak along at ground level because they will put down roots and your one plant can become many.

At the same time, deal to borer where you spot it. You will find the borer holes in the older wood. I tend to reach for the CRC or cooking oil to spray down the holes. It smothers them. Or you can use fly spray. None of these seem to harm the plant whereas the borer can ruin entire sections over time. It pays to keep replacement leaders coming through in case your main stems get too badly damaged.

Wisteria whips are very flexible when first cut and can be used for weaving in a similar way to basket willow.

Step by step instructions for pruning (with photos) here.

First published in the Waikato Times and reprinted here with their permission.

Plant Collector: zygocactus or Schlumbergera (probably truncata hybrid)

Winter woodland charmer - we refer to it as zygocactus

Winter woodland charmer – we refer to it as zygocactus

We have always referred to this plant as a zygocactus. Others sometimes call it a chain cactus (although that is confusing because there are other cacti referred to by that term also). In the northern hemisphere, it is widely called the Christmas cactus because that is the time it flowers, or sometimes the descriptive term of Crab’s claw cactus. In fact it is a schlumbergera, often referred to as a S. truncata hybrid although it is likely to have S. bridgesii in its parentage too. Not having any expertise in cacti whatsoever, I will wait for somebody more knowledgeable to tell me the dominant species in its makeup.

It is a cactus, but not a desert one and it is not prickly, hailing instead from the rainforests of Brazil, where it is epiphytic – using other plants as its host. It is widely grown throughout the world as a house plant and much favoured in hanging baskets because of its pendulous, arching growth, tolerance of semi shade and prolific flowering in the depths of winter.

If you are frost free, you can grow it outdoors and this is what we do. We have it perching and festooning throughout our woodland area where it is particularly joyous in the depths of winter. We only have the somewhat garish, cerise form which is the most common one around. Hybridists have extended the colour range considerably, even to oranges and yellows, but the different colours have not been as vigorous for us.

Being cacti, these are easy to propagate from the flat, jointed leaves. Just leave them to dry for a few days or longer before putting them into a fine, sandy mix.

First published in the Waikato Times and reprinted here with their permission.