Report of 2004-5 Sprouting Season (Long)

Leo A. Martin
Mon, 21 Nov 2005 10:36:04 PST
Hello All,

I thought I'd post my observations on winter-growing bulb sprouting 
since last season I finally had success after 4 years of near-total 
failure. (Fall-Winter 2004-2005)

This will be quite long, but if you have had trouble sprouting and 
growing on winter-rainfall bulb seed, you might find it interesting.

First, I live in Phoenix, Arizona, USA. I am in the northern Sonoran 
Desert. We receive summer thunderstorms between July and September, and 
gentle winter rains between November and April. Our average annual 
rainfall is 8 inches / 200mm, with about 60% in the summer. But this is 
very sporadic - we might have only 1 or 2 rains in a winter or summer 
season, or very much more.

Our relative humidity is very low unless rain is threatening - usually 
under 20%, and in our dry spring and fall, under 10%.

Daytime temperatures in the summer exceed 104 F / 40C between June and 
October. Summer night temperatures are over 85 F / 30C during this time.

Winter daytime temperatures are around 68 F / 20C when it's sunny - 
almost always - and 50 F / 10C when cloudy.

Freezes occur only at night during cloudless, still weather. The stars 
sparkle like diamonds on black velvet on these nights. At my house I get 
0-10 nights of temperatures below freezing, with lows for the past 
several years of 20 to 28 F / -7 to -1C.

I had read that African winter-growing bulb seeds were touchy as to 
overwatering and easy to rot. For my first several seasons I planted the 
seeds in sandy soil in 12 ounce / 325cc plastic beverage cups with holes 
punched in the bottom. I watered the pots when the top was quite dry. 
Almost nothing sprouted. Several species that did sprout grew for a week 
or two, then disappeared. (I haven't seen Gladiolus arcuatus, 
ceresianus, nor uysiae seed for sale since! And they all sprouted at one 
time but died for lack of water.)

Later on, from my reading, I realized much of the winter-rainfall region 
of southern Africa receives more rain and more regular rain that we do. 
And a friend of mine who visited South Africa during a winter told me 
most of the bulbs he saw seemed to be growing in water-filled roadside 
ditches. So, I resolved to give more water.

Around this time I discovered by accident that my mesemb seedlings (ice 
plant relatives, mostly from the winter rainfall portions of southwest 
Africa) performed better in styrofoam (polystyrene foam) beverage cups 
than in non-insulated cups or pots. Such cups are deeper and narrower 
than the plastic cups. I think the insulation makes a difference; on 
sunny winter days the soil stays cooler. Clay pots are useless in a 
low-humidity region such as here; they can dry completely within 1-2 
hours after watering on a sunny winter day.

So, I switched to 20 ounce / 600 cc foam beverage cups. These are about 
3 inches / 7.6cm wide at the mouth and 6 inches / 15.25cm deep. I write 
the name and my accession number directly on the cup with a black 
ball-point pen. I press hard so the tip leaves a deep groove when I 
write. The black ink is readable for at least 2 1/2 growing seasons. I 
label in advance one after the other cups for all the species I am going 
to sow in one session.

I did not put drainage holes in the cups when I planted the seeds. I 
think it is very important for the seeds to be very wet for quite some 
time in my climate in order to sprout.

I used my soil mix of 50% coarse builders' sand and 50% local soil, 
which consist of granite particles of various sizes. I would not use any 
organic material for the method I am about to describe because it would 
rot quickly.

I filled the cups about 4/5 full with my soil mix. Working with one cup 
at a time, I added some water to the cup to wet the top of the soil. I 
did not use enough water to soak all the soil - just the top portion.

I swirled the cup to even the soil surface. I let the water soak in, and 
used a spray bottle to wash the soil particles clinging to the inside of 
the cup back down to the soil. My goal was to have a very moist, very 
even soil surface. I use trays that hold 9 of these pots, so I prepared 
and moistened batches of 9 pots at a time.

I then sprinkled the bulb seeds evenly on the surface of the damp soil. 
I covered them with a 1 inch / 2.5cm thick layer of white quartz sand, 
which is sold here as sand for children's sandboxes. I used this very 
white sand so the tiny new sprouts would be easier for me to see when 
they emerged.

Without disturbing the sand too much, I carefully added water to the rim 
of the cup. As I worked on other cups, the water would soak into the 
previous ones, leaving sand exposed to air. I kept adding water until 
the cups were again completely full. Remember, I did not punch drainage 
holes in the cups, so they held the water. Finally I would have all my 
cups for that planting filled to the brim with water.

I set the cups in bright shade. They received no direct sunshine. They 
were under a solid cover so they did not receive rain.

I would let the water evaporate until the sand was dry at the surface 
but still damp below. This would typically take 4-5 days in our dry 
winters. Then I would again fill the cups to the brim with water.

When a good number of seeds sprouted in any one cup, I would then make 
drainage holes in the bottoms of the cups. From then on I never let 
sprouted seedlings dry out.

I began sowing in mid September and continued through November as time 
permitted. Since I only sowed one pot of each species I was unable to 
determine for any one species whether sowing earlier was better. 
However, I did plant about 10 cups of mixed winter-growing bulb seed 
from one large packet from Silverhill Seeds. I planted these between 
September and January. The ones planted early, when it was still nice 
and warm, produced many more plantlets than the ones sowed later. I have 
read that winter-growing bulb seed needs warm days and cool nights in 
the fall for best germination, and I would agree.

It took a lot longer for almost all species to sprout than I expected. I 
grow a lot of cactus from seed, and cactus usually sprout within a few 
days to a week or so. Not so the bulbs!

I did notice that sprouting occurred in groups, with many pots sprouting 
in the day or two after a good storm front came through.

Here are some of my results:

Species, Days to sprout
ambigua, 15-63
angustifolia, 31
attenuata, 31
curviscapa, 20-35
disticha, 38
odorata, 31
patersoniae, 31-42
patula, 36-42
ringens, 42-65
sambucina, 34-37
sp scented blue & yellow, 31-37
sp Various, 31-47
stricta White form, 31-60
stricta var regia, 53-63
vanzyliae, 31-38
villosa, 37-53

Species, Days to sprout
corymbosa, 32-33
fucata, 28-31
laxa 2001 seed, Didn't
occidentalis, 39
refracta, 39
viridis, 23-28

Species, Days to sprout
corrugata, 28
darlingensis, 41
heterostyla, 28
imbricata ssp bicolor, 58
inaequalis, 52
inflexa IBS, 63
inflexa Red fl form, 38
inflexa White fl form, 44
inflexa, 31
monanthos, 37
ovata, Didn't
purpureolutea, Didn't
radians, 69
schinzii?, Sprouted, time not recorded
splendidissima, Sprouted, time not recorded
spp A few unidentified species from the SW Cape, 37
tulbaghensis, 48

Species, Days to sprout
alatus, 64
carinatus, 66
caryophyllaceus, Didn't
dalenii, 12
gracilis, 60
griseus, Didn't
inflexus, 51
leptosiphon, Sprouted, date not recorded
liliaceus, 54
longicollis 2001 seed, Didn't
longicollis 2004 seed, 48
meliusculus, 86
orchidiformis IBS, 14
orchidiflorus, 37
permeabilis, 48
recurvus, 77
saccatus, 15
scullyi, 51
sp Madagascar Ihosy, 33
sp Madagascar, 38
sp Madagascar, 41
trichonemifolius, 92
tristis var aestivalis, Didn't
undulatus, 62
venustus, 27
virescens var virescens, 64
watermeyeri, 48
watsonianus, Sprouted, date not recorded
sp weed in flower pot, Didn't

Species, Days to sprout
bachmannii, 43
cucullata IBS, 51
cucullata Silverhill, 37
falcata, 59
grandiflora, 41
humilis, 37
luticola, 54
pauciflora, 33
vaginata, 35

Species, Days to sprout
bulbifera, 40
carnosa, 48
comptonii, 28
concordiana, 28
congesta, Didn't
contaminata large scented population, 28
elegans var suaveolens, 48
fistulosa, 63
kliprandensis, 36
latifolia, 52
mathewsii, 54
namaquensis, 28
orchioides, 43
orchioides var glaucina, 51
orchioides var orchiodes, 45
peersii, 55
polyphylla, Didn't
purpureo-caerulea, 28
pusilla, 60
pustulata, 23
reflexa, 53
rubida, 27
splendida, 28
trichophylla pustulate, 38
unicolor, 23
unifolia, 31
violacea, 28
viridiflora, 43
xerophila, 35
youngii, 69
zebrina forma zebrina, 23

Species, Days to sprout
sp mixed PBS, 30
anceps, 27
corymbosa, 53
fabricii, 34
falcata, Sprouted, didn't record date
jacquinii, 35
micrantha, 63
montana, 21
neglecta, 33
oreogena, Sprouted, didn't record date
plicata, 21
pyramidalis ssp pyramidalis, 26
silenoides, 27
sp, 25
spp, Sprouted, didn't record date

Species, Days to sprout
anomala, 52
atropunctata, 56
ciliata, 27
elliottii, 32
falcifolia, 33
fugax, 35
hantamensis, 53
huttonii, Didn't sprout
inclinata IBS 2001, Didn't
lugubris, 57
macrocarpa, 52
macronyx, 31
marlothii, Didn't
neglecta, Didn't
polyanthos, 32
sp PBS, 38
serpentina, 25-40
speciosa, 26-53
spathulata, Didn't
tricolor, 60
tricuspidata, Didn't
tripetala, 48
villosa IBS 2001, 48

Species, Days to sprout
punctata, Sprouted, date not recorded
stricta, 47

Species, Days to sprout
amoena, 34
aquatica, 48
atrandra v atrandra, 51
barkerae, 51
camerooniana, 32
citrina, 58
cruciata, 48
diversiformis, 58
flava, Didn't
gigantea, Didn't
hallii, 69
hantamensis, Didn't
hirsuta var hirsuta, 43
kamisensis, 32
minutiflora, 31
monadelpha, 54
monticola, 30
namaquensis, 58
neglecta, 59
obscura v subtestacea, Sprouted, date not recorded
rosea v reflexa, 43
sabulosa, 43
subfistulosa, Didn't
syringodeoflora, 54
tabularis, 30
tetragona, 32
tetragona v flavandra, 31
tortuosa, 67
toximontana, 36
triflora, Didn't
spp Silverhill, Sprouted, date not recorded

Species, days to sprout
deusta, 35
flabellifolia, 37
florentiae, 31
pallida, 35
securigera, 61

Walleria gracilis, 41

Species, days to sprout
aletroides, 25-33
coccinea, Didn't
fourcadei, 37
laccata, 33
meriana, 31-33
spectabilis, 32
tabularis, 31
vanderspuyiae, 24-29

Whiteheadia bifolia, 33-40

I might guess the seeds have lots of inhibiting chemicals that must be 
washed out before sprouting may occur. So, if you have had trouble 
before sprouting your seeds, I might suggest trying my method.

Leo Martin
Phoenix Arizona USA

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