Grow it yourself: pumpkins

It is pumpkin harvest time, not planting time. Alas the first buttercup pumpkin here (they are the smaller, green coated ones) was a terrible disappointment – watery and lacking flavour. Mongrel seed, even though it came from a major seed company. They are not the buttercups they were meant to be. There is a surprisingly large range of different pumpkin seed you can buy, but the pumpkin grower here plans to keep to the proven heritage varieties next year – grey ironbark for keeping and classic buttercup for eating fresh.

Pumpkins take up a huge amount of room for 3 to 4 months yet are very cheap to buy, so if you only have a small garden, you can probably grow higher value crops. Timing for planting is important. They usually go in as small plants when the soil is warming up but no later than December. You can accelerate early growth by planting them in a bed of warm compost. In good conditions, they then rocket away. Keep the water up to them as the fruit develops because these are thirsty plants. The young shoots of pumpkins, chokos and the like are a taste treat for quick cooking.

Pests and diseases include white fly and mildew but these come late in the season, after the fruit has formed. They should not have much effect on the yield and are rarely treated.

We grew Austrian Oil Seed pumpkins last year because they produce hull-less seed. They took up the usual large amount of space for a small seed yield and the pumpkin flesh was only stock food. We are back to buying pumpkin seed this year.

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

The Jury vireya legacy – first published in the RHS Rhododendrons, Camellias and Magnolias 2012 yearbook

The original plant of R.macgregoriae, collected by Felix in New Guinea

The original plant of R.macgregoriae, collected by Felix in New Guinea

Back in the 1950s when Felix Jury first became interested in vireyas, they were pretty much unknown in New Zealand with few enthusiasts internationally.

When Felix started raising seed and trying controlled crosses, he was just after anything that was new and therefore interesting. There was so little raw material to choose from in those early stages. He named maybe a dozen and with the passage of decades, about four of that dozen have stood the test of time very well and may still be around in another thirty years’ time. Unfortunately, the finer details on his crosses were never recorded so it is not possible to state with certainty which were Felix’s own crosses and which came from seed sent to him from overseas and were therefore just raised and selected by him. We know that the Australian, Tom Lelliot was particularly generous with seed and there were others from that country.

Golden Charm

Golden Charm

In 1957, Felix went plant collecting in the highlands of New Guinea. He brought back a few interesting plants. Ficus antiarus is still the most asked about tree in our garden. Schefflera septulosa is one of the most beautiful members of that plant family you will ever see. His form of Rhododendron macgregoriae is still rated as one of the best in circulation and, astonishingly, the original plant is still surviving. This is an achievement because vireyas are not noted for being long-lived in our climate. It was that plant of R. macgregoriae which gave rise to one of Felix’s best cultivars – Golden Charm (R.macgregoriae x Princess Alexandra). We still rate it highly after several decades. The foliage is dark and glossy, the new stems are red, the habit is compact and healthy and the many flowers, while relatively small, are in good sized heads and attractive apricot to orange tones. It is also relatively hardy.

Buttermaid

Buttermaid

With the benefit of hindsight, we now wonder whether Felix’s other two notable R. macgregoriae hybrids, Buttermaid (R.aurigeranum x R.macgregoriae) and Orangemaid (R.laetum x R.macgregoriae) might not in fact be Lelliot seed, raised and selected by Felix. Alternatively, he may have been sent pollen. Mark is not at all sure that Felix had R.aurigeranum at that stage and he is sure he did not have R.laetum. The R.macgregoriae parentage shows dominance in both the flower form and colouring of these selections but hybrid vigour makes them more reliable and tidier garden plants. Queen of Diamonds (R.viriosum x R.macgregoriae) was indubitably Felix’s own cross, a pink version this time but rather too tall and leggy to be of great merit. [Apparently R.viriosum was misidentified for 70 years as R.lochiae. Most records use the R.lochiae name when it appears that they are all in fact R.viriosum. I will defer to those with a great deal more expertise in this matter and have according changed to using R.viriosum.]

Satan's Gift planted by the Schefflera septulosa

Satan's Gift planted by the Schefflera septulosa

Satan’s Gift (R.konori x R.zoelleri) and Silken Shimmer (R.konori x Dr Herman Sleumer) were selections from Australian seed, raised by Felix. These were spectacular for their day, being big and lush, colourful and fragrant. Satan’s Gift is the stand-out plant which has passed the test of time and is still a wonderful performer. The name amuses us. Felix was a completely non-religious man and to him, Satan merely evoked hot colours. Over the years, more devout nurseries have clearly had a problem with the name and this cultivar has been marketed variously as Jury’s Gift, Satin Gift and, best of all, Santa’s Gift. One wishes nurseries would understand that it is fine to reject a plant because of ethical issues with the name, but it is not acceptable to rename it willy nilly.

Cherry Pie

Cherry Pie

Felix was very taken with the big, scented blooms of R.konori and his own hybrids were the pink Cherry Pie, red Hot Gossip – both sister seedlings of a viriosum hybrid x R. konori – and Lipstick. Cherry Pie is particularly lush and has good bushy, spreading growth along with a good flower (though much of the scent has gone) and we still rate it as a good garden plant.

Red Rover (R.viriosum x R.javanicum) is another of Felix’s early hybrids that we continue to rate for its bushy growth habit, healthy characteristics and plenty of good red flowers in a mid-size. However his R.jasminiflorum hybrid called Lullaby has dropped off the radar now and, while a good performer, Lulu (unknown) has probably been superseded by modern selections with more flowers to the truss.

By the time Mark started hybridising vireyas, there was a veritable explosion of recently discovered species and newly imported species becoming available. He collected every single one he could lay his hands on at the time and propagated a few to distribute to collectors. Our nursery records show that we produced over 60 different species at that time, and very difficult most of them were too. The death rate in the species was far higher than in the hybrids, both in the nursery and when planted in the garden. It was with some relief that we decided after a few years that the few collectors in the country (there were probably only 5 or 10 of them) had everything we held so we stopped feeling obliged to produce them. Similarly we decided that it was not critical to keep every species represented in the garden. We have never coveted a national collection of any plant genus because we would prefer to garden with plants which justify their position as being garden worthy. Only some of the vireya species perform well for us – we would be sorry to lose varieties such as R.himantodes, R.goodenoughii, R.taxifolium, R.hellwigii, R.macgregoriae and R.konori but many of the other species are either too difficult for us to keep going, or not worth the effort (R.inconspicuum, we have always felt, was particularly well named).

Sweet Cherry

Sweet Cherry

So Mark had a much bigger plant palette to work with and this included an ever increasing number of new hybrids as well as the species. Vireyas were suddenly a fashion plant in New Zealand. They were seen as a wonderful alternative for warmer areas of the country where the hardy rhododendrons do not thrive. Added to that, in a country where we would like to be tropical but aren’t, vireyas fitted that exotic look and often obliged by flowering throughout the year. From being an unknown plant family with no market at all, they were a gardening sensation for a few years in the nineties. Fashions change and vireyas are no longer as popular as they were – they are somewhat harder to keep alive, let alone looking good, than many people realised. But in those heady days, there was an insatiable demand for new varieties which had large luscious blooms with heady fragrance and large, heavily felted foliage. Unfortunately, this sometimes meant using breeder parents which, with the passage of time, have not proven to be particularly resilient in our climate.

Mark was also keen to extend the flower form of vireyas into full trusses which more closely resemble the hardy rhododendrons. Many of the species and early hybrids are quite sparse in their flowering and have few flowers to the truss. He also wanted to explore what could be done with colour.

Mango Sunset

Mango Sunset

With the benefit of twenty years experience, he has gone full circle and come back to the point his father reached earlier – a conclusion that it is more important to produce healthy plants which stay alive, with compact growth and masses of flowers as top priorities. More hardiness and less flash and dash, one could say. This tends to mean sacrificing individual bloom size, foliage size and often fragrance. It may end up that his R.macgregoriae hybrid, Mango Sunset, proves to be one of his best. While he achieved the much fuller truss, he was looking for, it is just a good all round performer without being spectacular.

Jaffa

Jaffa

Market demands meant Mark made the same mistakes as many other vireya breeders – selecting new cultivars on the beauty of their blooms and on initial performance as a nursery plant. The test of longevity rests, for us, on long term health and performance as a garden plant. More than we would wish have fallen by the wayside. Candy Sunrise (R.konori x Halo series) had beautiful, big fragrant flowers with good colour but was very susceptible to phytopthora. Ditto the red Sweet Cherry (R.konori x R.hellwigii) – wonderful as a garden plant but not easy in the nursery, Strawberry Fields (Satan’s Gift x R.brookenaum) – gorgeous big red flower but leggy growth over time and inclined to die, Orange Sparkles (R.retusum x R.macgregoriae) and cute little Jellybean (Red Rover x R.stenophyllum). Frosted Candy, another of the R.konorii x Halo series hybrids, is performing very well as a large garden plant (now two metres plus which is large for a vireya) and it has huge blooms, but again is difficult in the nursery with an unacceptably high death rate from phytopthora.

Jaffa (Halo series x R.javanicum) is in the right direction for a full truss. There are now up to 15 large blooms per flower head (which is a big increase from the 2 to 5 range of many of the species and early hybrids) and a good, strong orange combined with large, lettuce green foliage. It is more frost tender and sensitive than the tougher cultivars (which tend to be those with R.macgregoriae, R.viriosum or R.saxifragoides in their parentage). It certainly has the right tropical look and is a better nursery plant than many.

Pink Jazz

Pink Jazz

Pink Jazz (R.konorii x Halo series) is another splendid large grower with enormous blooms – bright pink with a central star of cream and scented too. It also has the stand out feature of deep maroon new growth and even the old foliage keeps the burgundy tint. It is not easy as a nursery plant and it is too big for many gardens, but the plants we have in our garden are standing the test of time. We have a special fondness for this one. Mark rarely names plants after people, but this one is for our older daughter who, in her teens, was called Jazz by many friends and who nursed a penchant for wearing hot pink.

Mark has always been lukewarm about Peach Puff ([R.phaeopeplum x R.leucogigas] x R.viriosum selfed) because he regards the pastel peach colouring as insipid. It was an interior fashion colour a decade ago and I still find it very pretty. Again the truss is satisfyingly full with big blooms, good scent and felted foliage.

Sweet Vanilla

Sweet Vanilla

Of that type of larger flowered, scented hybrid, Sweet Vanilla ([R.leucogigas x R.viriosum] x Silken Shimmer) is probably the best garden plant for fragrance. Its flowers, while not huge, are a good size, opening soft pink and fading out to cream. This is one plant which garden visitors regularly ask about when in flower – always a good indicator of showy performance. Sherbert Rose (Hot Gossip sister x R.herzogii) matches Sweet Vanilla for scent and it is very floriferous but the small tubular mid pink blooms simply aren’t showy enough for most people. We still like it because we don’t want only big showy or blowsy vireyas in the garden, but we stopped producing it commercially because scent alone was not enough to sell the plant.

Practical Matters:

Preparing vireya cuttings - wound both sides

Preparing vireya cuttings - wound both sides

Vireya rhododendrons must rank amongst the easiest of the woody plants to propagate but one of the hardest to produce commercially. Neither are they bullet proof as garden plants. As long as you have firm, green material, it is easy to get cuttings to root. You don’t even need rooting hormone. In fact it is so easy that we routinely showed customers how to take autumn cuttings so they could have back up plants lest their specimen get taken out by a hard frost or wet roots. The one critical issue is to remember to have a generous sized cutting and to take the sliver off two sides of the stem (wounding). Vireyas put their roots out from the exposed cambium layer and having two wounds gives a more balanced root system and therefore more stability. It is keeping them alive after rooting which is the tricky part, especially in nursery production. Vireyas are not only frost tender and deeply intolerant of wet feet (sodden root systems), but they are vulnerable to pretty much every strain of phytopthora and a fair range of other diseases common in nursery production. In the wild, many of the vireya species are epiphytic or semi epiphytic which is an indicator that their roots need open conditions. This is what fits them to a role as permanent pot plants though they appear to last better in pots which are more permeable (terracotta or wood) than in containers which are impermeable (glazed pottery or plastic) and dependent for drainage on one or two holes in the bottom. When producing commercial runs of vireyas, we maintained a rigorous spray programme to keep disease at bay. Even so, we tolerated a far higher mortality rate in nursery plants than we would in any other crop. We have always produced them outdoors, under protective shade cloth and overhead irrigation – identical conditions to most of our nursery crops.

Vireyas tend to put on a lot of top growth, supported by small, inadequate root systems (an indicator of their epiphytic origins), and new growth is often very soft and brittle. As nursery crops in our climate, they grow very rapidly at all times of the year and it is possible to get a saleable plant through in half the time of a hardy rhododendron, but they are correspondingly more vulnerable to damage by mishandling and disease.

Vireyas used in a garden border

Vireyas used in a garden border

We are blessed with a climate which enables us to use vireya rhododendrons as garden plants. We are not entirely frost free so we use them on the woodland margins where temperatures may get cool but never cold enough to cause significant damage. Any frost at all can burn the most tender varieties which includes anything with R.leucogigas, R.konorii, R.hellwigii and sometimes even R.laetum in the breeding. The hardier types will take two or three degrees of frost without damage but more than that can be a problem. Get it up to five degrees of frost and plants can be killed stone dead. The beauty of vireyas as garden plants is that they do not have a set flowering season so if you have sufficient numbers, there are always plants in bloom – even in the depths of winter. Added to that, they are tolerant of hard pruning so easy to renovate. Even when cut back to bare wood, most will force out dormant leaf buds from old wood and can be bushy and fresh again within a matter of months, even if it takes longer for them to set flower buds. It is a misconception that vireyas are all tropical plants. While natural habitats are often in the tropical latitudes, they are in elevated sites which cool the temperatures.

With their climatic limitations, vireya rhododendrons will never have the geographic distribution of hardier plants and, no matter how good the hybrids, they are unlikely to achieve international standing. There is a long way to go yet in breeding reliable cultivars which are likely to stand the test of time but it is certainly interesting to have been in from the early days on the development of new selections and Mark will continue to work with them here, albeit on a rather casual basis.

A promising  lemon seedling - the breeding continues

A promising lemon seedling - the breeding continues

The first instalment of this series was the 2011 article on Jury rhododendrons.

Of naked ladies, autumn crocus and so-called autumn crocus.

Just for the record, and in light of finding myself in print with some incorrect information which I didn’t actually write, I offer the following clarification.

The true autumn crocus is indeed a crocus

The true autumn crocus is indeed a crocus

The true autumn flowering crocus is in fact a crocus. There are many different species in the genus of crocus, some flowering in spring and some in autumn. Generally, crocus flower around the same time their foliage appears. We don’t have a species name on this pretty autumn crocus in our garden. Trace the botany of crocus back and they are part of the subfamily of Crocoideae, the family of Iridaceae and the order of Asparagales.

Colchicum autumnale

Colchicum autumnale

Colchicum autumnale flower about the same time for us, but the flowers appear a long time before the foliage so they are sometimes called naked ladies. Equally, they are sometimes referred to as autumn crocus but they are not. Again it is a big genus with many different species but they come from the family of Colchicaceae and the order of Liliales.

Sternbergia are not autumn crocus either (Photo credit: Meneerke bloem)

Sternbergia are not autumn crocus either (Photo credit: Meneerke bloem)

Sternbergia are sometimes referred to as autumn crocus but they are no more autumn crocus than colchicums. In fact they are more closely related to narcissi than crocus (a fact I discovered from the Pacific Bulb Society) and they are closely related to amaryllis. However, they flower with their foliage and their blooms, generally yellow, resemble a crocus in form. We have sternbergia in the garden here but they don’t flower overly well for us, possibly because they are essentially a Mediterranean plant which likes a hot, dry summer.

Amaryllis belladonna - the other naked ladies and closely related to sternbergia

Amaryllis belladonna – the other naked ladies and closely related to sternbergia

Also widely referred to as naked ladies are Amaryllis belladonna or the belladonna lilies that are mostly seen as roadside plants here. The genus is amaryllis, the species is belladonna (and there is only one other species in that genus) but the sub family (Amaryllidoideae) and then family (Amaryllidaceae) are the same as sternbergia. Trace them back another step on the Linnaeus chart and you find they are from the order of Asparagales which is where they meet the family tree of crocus – quite a long way back, botanically.

The bottom line is that the true autumn crocus is indeed a crocus, though it may be one of many different species.

Amaryllis belladonna (or naked ladies) are usually seen as a roadside flower

Amaryllis belladonna (or naked ladies) are usually seen as a roadside flower

In the garden this fortnight: April 26, 2012

A fortnightly series first published in the Weekend Gardener and reproduced here with their permission.

The pretty Moraea polystachya has a long flowering season

The pretty Moraea polystachya has a long flowering season

We are not noted for autumn colour here. I can’t think that anybody has ever said: “Oh but you simply must go to Taranaki to see the autumn display.” The trigger to deciduous plants to turn is temperature related and we drift so imperceptibly from summer through autumn to early winter, that even plants renowned for their capacity to blaze with colour are usually a disappointment. Besides, we are so verdant and green and our native plants are all so resolutely green that all we can do is to admire the occasional single deciduous specimen. Generally it is inland areas with drier climates and much sharper variation in seasonal temperatures which put on the big displays.

However, our autumn is marked by much smaller, pretty pictures of autumn bulbs. We garden extensively with bulbs. In a large garden with some huge trees, it is the dainty, often ephemeral pictures which give the charm and detail. Autumn flowering bulbs are harder to find for sale because most people don’t think beyond the more common spring bulbs.

Cyclamen hederafolium - the easiest of the species in our climate

Cyclamen hederafolium - the easiest of the species in our climate

At the moment, it is the pink and white Cyclamen hederafolium, blue Moraea polystachya (autumn peacock iris), a rainbow of colours in the ornamental oxalis, bold lilac colchicums (often incorrectly referred to as autumn crocus), the real autumn crocus and the beautiful hybrid sarniensis nerines which are carrying the season in the rockery. Out on the roadside, the belladonna lilies are in bloom. Some, like the colchicums, do not flower for long but are very showy. Moraea polystachya is a gem of a bulb. It flowers down the stem so it has an exceptionally long season stretching into months rather than weeks. It can seed down but is easy enough to thin out if necessary.

Cyclamen hederafolium (formerly known as neapolitanum) is the easiest and most reliable of the species cyclamen. It too has a long flowering season, followed by attractive, heart shaped leaves with white markings. It combines very well with black mondo grass and in places we have English snowdrops (galanthus) to come through in late winter, extending the seasonal interest amongst the cyclamen foliage.

Top tasks:
1) Cut off all last season’s leaves on the Helleborus orientalis and remove them to the compost heap. We have done this for many years now, following the advice from Terry Hatch at Joy Plants. It removes any build up of aphids and it means that the flowers are highly visible as they come through with just delicate new leaf growth. As the season progresses, the new foliage takes over and fills the whole patch. Timing is important – if you leave it too late, you have to trim carefully around all the emerging flower stems.
2) After raking off the hellebore foliage, I will weed out the rash of germinating seedlings and then cover the whole bed with a mulch of compost to a depth of about 3cm. This feeds the soil and discourages weeds. Hellebores are one perennial that is best left undisturbed. It is better to raise seed than to try and divide existing clumps. They can sulk for years before recovering.

The Nerine sarniensis hybrids are a real autumn feature in the rockery

The Nerine sarniensis hybrids are a real autumn feature in the rockery

Tikorangi Notes: Friday 27 April, 2011

The Taxodium ascendans nutans has turned orange on one side only

The Taxodium ascendans nutans has turned orange on one side only

Latest posts:

1) Our garden diary for the fortnight (as published in the Weekend Gardener) and mostly on autumn flowers.

2) Slightly nervously, I offer up a carefully crafted opinion on the current state of garden assessments with reference to the New Zealand Gardens Trust.

3) The most lovely schefflera I know in Plant Collector this week – Schefflera septulosa. Not that I pretend for one moment to be an expert on scheffleras, but it is a beauty.

4) Feijoas feature this week in Grow It Yourself.

5) Revisiting Outdoor Classroom (in conjunction with the Weekend Gardener) – how to deal with large clumping plants. We tackled a massive Curculigo recurvata but we might equally have tackled an astelia or a flax.

It is time to gather magnolia seed. I mentioned in an earlier Tikorangi Diary that we have been asked several times about odd growths appearing on magnolias. Each time it has been seed pods – photographed below for reference, now that they are ripe. These pods will open in due course and produce the red seeds, looking like the michelia seeds in the lower photograph. The soft red casing is then rotted off to reveal a black seed.

Michelias these days are more correctly known as magnolias – a reclassication based on scientific analysis. We persist in referring to them as michelias for clarity, while acknowledging that we are probably incorrect botanically.

Magnolia seed pods

Magnolia seed pods

Michelia seed

Michelia seed