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Drosera filiformis leaf cuttings with plantlets
floating in pure water. |
The second requirement for leaf cuttings is
an appropriate medium for the leaves to live until they produce plantlets. Fortunately
there are lots of options here.
The cleanest medium for leaf cuttings is pure water. Float
the leaves, tentacle side up in a cm or so of pure water in a small
jar sealed with plastic wrap. If the leaves are too long to fit,
cut them into whatever length does fit. Make sure you use pure
water. That is distilled or reverse osmosis water. If the water
gets cloudy, change it. The advantage of water over other methods
is the leaves will survive longer in the relatively sterile water.
This is especially important for ones that are slow starters. When
the plantlets have small roots, plant them in their preferred medium
such as peat/sand.
Other mediums to use for the leaf cuttings are live sphagnum,
dried long fibered sphagnum, peat, peat/sand, or sand. In other
words just about anything that you can grow the adult plants in.
The main criterion is that the leaf cuttings need to kept from
drying out and should be partly covered by the medium to keep them
in contact with it. You can put pots with the leaf cuttings in
plastic bags or sealed terrariums, whatever will keep the humidity
at 100%. The advantage of using mediums with peat are the peat
can somewhat provide nutrients to the leaf and earlier to the plantlets.
Live sphagnum is thought to protect the leaf cuttings from mold
and provides a somewhat acidic medium. And you can leave the plantlets
in the pots for some time as they are already in a preferred growth
medium. The disadvantage of these media is they contain molds,
cyanobacteria, and other organisms that may interfere with the
health of the leaf cuttings. Also the leaf cuttings may move and
dislodge themselves so you have to watch things more closely.

Drosera prolifera is an easy species
for leaf cuttings. The old leaves are red but still with dewy
tentacles 4 months after being cut off the plant. |
Make sure you put labels on the jars or tags in the pots with
species name and other information along with the date. The date
on the tag is very important. It is going to seem like an
eternity until something happens in the pots and you can confirm
that by reading the date on the tag.
The rest of the requirements for leaf cuttings are environmental:
light, temperature, and time. The leaf cuttings
need lots of light but you don't want to roast them. It is usually
safe to put them under fluorescent lights but no closer than 8
inches or 20 cm. In a greenhouse it may be best to put them under
the bench or in a shaded location. However there are species such
as the tropical D. petiolaris group species that want rather warm
temperatures.
Now comes the real hard part: waiting and waiting and waiting. Don't
overdo opening the bags. And don't stick your face into them. Remember
we are trying to avoid fungus. Nothing much is going to happen
for the first month or so. D. filiformis
and D. binata may explode out fairly quickly the second month
but others like D. slackii could hang on for 5 months and then
condescend to do something for you. Maybe. Not all leaves will make
it. You may want to remove ones that totally turn brown or get fungus.
But don't give up and definitely don't begin mourning if there is
any green or red left on the leaves.
The thing that amazes me most is where the young plantlets sprout.
It totally blew my mind to see the D. spatulata plantlets
sprouting from the center of the leaf. I was told me that is
what would happen but I still wasn't prepared for it. Right out
of the center of the leaf... Other species like D. prolifera do
sprout near the leaf edges where I expected but they will do
it from leaves that look like toast! And then there is D.
binata. Stand back! The plantlets
were spaced one or two mm apart on the leaves. But most Drosera take
their time, produce a few plantlets, and grow slowly.
John Brittnacher |