Larry Stoter wrote:

Last September, in France, I came across a splendid Canna. Very splodgy,
orange/creme flowers with variegated red/green leaves. Some of the
flowers had set some good seeds - which I picked.

Seeds are quite large and hard - I presume they'll need cutting to stand
any chance of germinating. Has anyone grown Cannas from seed?
Suggestions? What are chances of germination? How long until they
flower?

Sounds as though the variety you have collected may be 'Cleopatra' a
hybrid that can have red and green, all red or all green leaves as
well as red and yellow, all red or all yellow flowers. It is quite a
curiosity and great fun to grow. However, it should be noted that
Canna hybrids do not come true from seed and although some of the
progeny may resemble the parents, they are rarely as good.
Nevertheless, it is fun to grow a few this way and you never know, you
might just get something that is even better. The best time to sow is
in January or early February , which will give the plants a good 14 -
16 weeks growing time before they can be hardened of for planting out
of doors.

Thankfully Cannas are extremely easy to grow from seed if you observe
a few easily followed rules. The seed coats are bullet hard (hence
the occasional common name of 'Indian Shot'). The best way of
enabling water to penetrate this seemingly impermeable barrier is to
nick the seeds, by holding them in a pair of pliers and using a file,
carefully cutting into the coat until you reach the white endocarp
within the seed. Only the tiniest amount needs to be exposed and it
is better to file too little away than too much. If you look at the
seed carefully, you will see a scar (hylem). It is through here that
the growing shoot will break through. You should file the coat on the
opposite side to the scar in order to avoid damage to the embryo.

The next step requires a bit of bravery, so you'll need to 'grit yer
teeth'. Place the seeds in a cup or beaker and pour freshly boiled
water over them. As soon as you hear the seed coats starting to
crackle and pop, immediately add enough cold water to cool them down
to luke warm. The seeds should then be allowed to soak for 24 or more
hours in a warm place - an airing cupboard is ideal. Inspect the
seeds and most should have swollen to almost double their original
size after 24 hours. Sow these just below the surface of lightly
moist, sterilised, soil-less compost and maintain temperatures of 25C
or higher. Germination will take no more than 48 - 60 hours and don't
be surprised to see first shoots appearing in as little as 24 hours.
Those seeds which have not swollen immediately, can be left to soak
for another day or so before sowing. In the early stages, seedlings
need to be kept at around 21C to prevent damping off.

Canna seedlings need lots of light and should be left to grow to the
second leaf stage before potting up into 8 - 10cm, diameter pots.
Once they have established well, temperatures can be gradually reduced
to 15 -18C. Pot on as necessary and keep the young plants moving by
applying half strength liquid feed at 14 day intervals. By May, the
seedlings should be in 25 -30 cm. diameter pots and will be ready for
hardening off for planting out in the first week of June. If you
start early enough in the year and maintain good growing conditions,
you can expect first flowers by July or early August.

Dave Poole
TORQUAY UK