TOW Nerine Part 1
Hamish Sloan (Mon, 28 Apr 2003 13:42:11 PDT)

Dear All,

Hope you find this of interest.

TOW - Nerine

First, some introduction to myself. I did not give this earlier, as I was
not (I almost put "au fait" but perhaps I should not use French phrases
here. Things French are not exactly popular in these or certain other parts
of the world! And rightly so in my view.) familiar with the customs of
these parts.

I garden in middle Southern England, on the warmer end of Zone 9. Severe
frosts and snow are rare, but can catch you out, if you are not watching.
Generally wet, but with occasional dry periods, so storing rain water is
handy. It is the wet that comes with these not so cold temperatures that is
the major problem in doing the damage to bulbs of all kinds. Our plot is a
little under one third of an acre. The soil is a fine alluvial clay
containing a very little fine sand (about 2%, almost not noticeable unless
you swill some soil with water to wash away the clay loam) about a spit
deep (i.e. a spade's depth; use this word spit elsewhere?). The subsoil is
heavy clay with flints aplenty. When we first came to this home 30 years
ago, I filled a 1.5 ton truck with the larger flints picked out in the
first couple of months when I cut the vegetable plot into the far end of
the back garden. I have gardened for over 50 years and as that gardening
started when food rationing was still in place, vegetable and later fruit
growing were my start and still take my time. The soil is acid and suits
magnolia (with some attention to drainage being a great plus for these),
camellia, rhododendron, pieris and hydrangea. I have a few of each of these
and all of them have one blessing. In general, they look after themselves!

The soil is badly drained as a result of the clay beds but fortunately we
are on a slight slope so that no water accumulates on the surface. However,
having improved the drainage of the vegetable garden particularly, when I
irrigate in dry spells in summer, I can see the water run off at the lower
end where the water has gone down to the clay layer and then run along the
top off this bed.

This poor drainage makes for difficult conditions for many bulbs. I have
seen some of your comments about tulips not being worth the bother for more
than one year. I certainly find that tulips and daffodils of various
cultivars will flower the first year and then take time to settle down to
growing and flowering every year. Some 'Pheasant's Eye' that I put in about
5 years ago have just about settled in to regular flowering. Add the frost
and wet combination in winter and hardiness becomes an important factor.
That other common hardy amaryllid, Crinum x powelli does well by the East-
and West-facing house walls where the usual builders rubbish provides some
good drainage.

Nerine

I picked up on nerine about 25 years ago, apart from a few Nerine bowdenii
which survived outside. Most of my collection of the non-hardy sorts are
named hybrids. The dozen species are all fairly recent additions. There are
two great advantages of growing nerine from the practical point of view.
First, they need very little heat in the winter months - temperatures just
above freezing and they will survive, though this is not necessarily the
best temperature to keep them with a good flower show in mind. So that
keeps cost down (a point I particularly appreciate since at one time I grew
a number of orchids). Second, they can take a certain amount of neglect.
They do not need constant attention to watering. This is particularly
useful at holiday times as none of my neighbours are "specialist" growers
in any sense!

However, the greatest appeal of nerine is in the aesthetic sense. There are
other flowers which have the refractive and reflective combination that
gives them a sparkle, but for me there is nothing as good as being greeted
by "Lady Cynthia Colville" on a sunny October day when her flowers facing
the sun have a sparkle to gladden any heart. It is this flowering period
that is a part of their specialness - they come at a time of year, the
early to late autumn and in a few cases into mid-winter, when there are
fewer plants in flower. They are also long-lasting flowers on the bulb or
as cut flowers. This particularly applies with Nerine bowdenii outside,
here, when its pink flowers are a very welcome last glory before winter
arrives. The degree of sparkle varies from one plant to another. The old
Victorian gardeners used to refer to gold or silver dusting on the petals,
but it is not particles on the surface. The cells making up the surface are
so shaped that the light rays are refracted, giving partial effect to
colour of the returning rays, and reflected from the base of the cell,
adding a further turn to the colour effect. So each cell adds its little
piece to the whole. Having various sized cells in different species or
cultivars, there is then the appearance of different sized "sparkle units".

A second variation in nerine lies in the colour variation. Particularly
with the cultivars, there is the potential for three units of colour on
each petal; a ground colour with the edge colour most often along the sides
of the whole petal and a central stripe which may not lie on the whole of
the petal from base to tip. In some cultivars, the stripe or edge or both
may be missing. Colours vary from through shades of pink to red.

The third variation lies in the degree to which the petals reflex. the
better looking flowers tend to be more reflexed.

The fourth variation lies in the crinkling of the petals, with a wide
variation from none to those heavily crinkled at the tips and on down the
sides of the petals towards the base.

Cultivation

Except for N. bowdenii and a few others such as "Pink Triumph", nerines are
not hardy enough to withstand frost. Mine grow in a greenhouse kept
frost-free, generally at a minimum of about 45 F, through the winter. Such
is the vagaries of our weather that temperatures are often above this even
over night in winter. More warmth makes for better vegetative growth. I
have not specifically observed deleterious effects of excessive
temperatures of flowering pattern, though temperatures below about 40 F
seem to discourage flowering and I would conjecture that high temperatures
may be bad for the following years flower display. For the winter-growers,
foliage is beginning to die down about now. I keep it going for as long as
possible and feed well with Phostrogen liquid feed. Pots are tall square
pots, 12 cm square at the top, tapering slightly to the base and 20 cm
tall, and I aim for 3 flowering size bulbs in a pot. The slight
overcrowding this leads to as offsets develop does not seem to be
deleterious but the extra depth compared to normal pots appears to be an
advantage. The square compared with the usual round pots also save space as
they can be packed closer together without detriment to the plants. As for
any greenhouse user, there is always a shortage of space. These pots have
been produced here for the nursery trade for such as smaller roses and
other shrubs. They are 2 litre capacity, about midway between a standard 6
and 7 inch pots. (The company that makes them has a three litre version on
the way. I wish they would make a smaller version, say 9x9x15, for growing
on offsets.) Compost is my own mix of one part each of garden soil,
leafmold (or peat if it is not available), vermiculite (standard builders'
grade) and grit (3 to 6 mm particle size). The soil and leafmold are sifted
through a quarter inch sieve. I add fertilizer to bring the mix to John
Innes 3 level but with double the amount of lime instead of limestone to
allow for the acidity of my loam and to avoid buying expensive limestone -
I am, after all a Scot and a bit tight with my cash. (Aberdonians have the
reputation of being the tightest and I'm not Aberdonian. Besides, the
definition of an Aberdonian is a Yorkshireman with the meanness taken out.)
I also add 20 gm of Supergel (poly-N-acrylamide which swells to about 100
times its volume to hold on to water), 20 gm of trace element frit (many
amaryllids send out deep roots which delve into environments high in rarer
metals) and about 40 gm of iron filings (I'm a former long time
chrysanthemum grower) to each bushel of compost. The whole is very porous
and I ensure that I water frequently but never leave the pots standing in
water. These square pots have raised feet at the corners so that drainage
is ensured and 24 will sit comfortably in a Growbag tray on the greenhouse
bench. During the growing season, I water with a liquid fertilizer on every
occasion, when the pots dry out from the previous watering. Overwatering is
death to the roots and the bulb will regress. I hold no truck with those
who have advised in the past that nerines do well on a starvation diet.

Most of my nerines are autumn-flowering, winter- and spring-growing, and
summer dormant. Watering essentially stops as the leaves die down and the
bulb passes into dormancy but for successful flowering, it is necessary to
ensure that the compost does not dry out totally. This is common to a
number of other amaryllids. It is necessary to maintain the roots in turgid
condition or the incipient flower buds abort. So the plants get an occasion
sprinkle through the summer according to temperature and dryness. Rain
water only is used - it's not often we run short of that! About the end of
July or into the first couple of weeks of August, I will give a heavier
watering and then wait for the flower buds to show. During the summer the
bulbs are shaded to prevent them getting too hot - baking is not required
for good flowering results. I have on occasion moved them outside into
protected frames with good ventilation, and shading as need be, to keep
them cool, but the size of my collection makes this a bit of a chore now.

Water moderately as the flower scape develops. Keep the volume of water low
until leaves develop. This may be as the scape grows or after the scape has
reached full height or even after the flowers have opened and begun to
fade. Where a bulb produces more than one scape, I find that they usually
come in sequence and the leaves will develop considerably after the first
scape is well advanced; thus the following scape will be on a well-leafed
bulb. And hence the merry round.

Fertilization is generally easy for the species and many of the cultivars.
Some cultivars are particularly poor at seed set or as pollen parent or
both. The seed grows readily and the fruit will fall open when ripe enough.
The ripe seed are green; I am still surprised by the wide variation in size
of the seed obtained, often within the same pod, and yet still being
viable. The seed will germinate soon after ripe. I have never tried keeping
seed by cooling or drying. Sow on the surface of a fine gritty compost and
the seed sends out a radicle to pierce the compost and form a bulb below
the surface. Some radicles seem to be weak and I give them a helping hand
with a slit in the surface of the compost and manouevre the radicle into
it. The first leaf will come up fairly soon after. Keep the bulblets
growing, potting up only when the seedling pot gets near to crowding to
minimize disturbance. Until they reach flowering size, there is no need for
any dormant period, though of course flowering size varies from one specie
or hybrid to another and it's a bit of a guess-and-by-golly-game. But at
least two years and fairly safely three years may be allowed to get to
flowering size.

Part 2 with some comment on species and cultivars follows tomorrow. I'm
late!

Regards to All,

Hamish Sloan
Newbury, Berkshire, England,
Wettish Zone 9.