On 24/08/2014 23:29, Bertie Doe wrote:


"Spider" wrote in message ...

On 24/08/2014 20:29, Bertie Doe wrote:

My 2 plants are 4 and 5 years old. Hadn't thought about re-potting.

The planting medium looks like forest bark, is this correct?


Mmm .. maybe it's time you thought about repotting, then. The
planting medium must be well-drained and, yes, it does look like the
forest bark one mulches borders with. However, I use a proprietory
orchid compost which has a high bark content. I also use clear
plastic pots. Although many believe this isn't essential, it does
mean the roots get some sunlight (they can photosynthesise) and it is
also clearer when the plant needs repotting.

It is arguably better to pot on in Spring but, if a plant really needs
potting up, I believe it is better and kinder to pot up when needed.
I've never had a problem with an out-of-season potting up. Indeed, it
won't be long before I'll need to pot up about 10 of mine.

Thx didn't realise there was a special compost. I'll pick up some orchid
feed at the same time.






When you pick up the compost, have a good feel at the bag so you know it
has a reasonable quantity of bark. There seem to be slightly different
grades, although this appears to be accidental since there is no grading
on the label. I bought a bag in a hurry a few years ago and there was
less bark than usual, much of it being coarse composted bark, and some
of my Phalaenopsis failed due to lack of drainage. This less
well-drained compost was suitable for my Cambrias and Paphiopedilums
(which don't hold onto water as well as Phals) so the remainder wasn't
wasted.

If you look at your Phalaenopsis roots, you will see they are quite
fleshy (they should be!) and this enables them to hold on to water in
the manner of a succulent, though not for so long. Many other orchids -
cambrias, burragenea(sp?), odontoglossums, oncidiums - have much finer
roots, so cannot store water for long. Paphiopedilums have fairly thick
roots and fall between the two. Looking at the roots gives you a
helpful guide to their watering regime. This will be useful to you when
you increase your stock (you will!).

Going back to Phals, it's worth noting that if the end of their fleshy
roots is reddish, this is a sign of stress.

When you pot up your Phals, water them as usual to settle the new
compost around their roots, but don't feed straight away. Just because
when you move house you can't wait to put the kettle on and scoff half a
packet of digestives, doesn't mean your Phals share the same
requirement! Let them settle in first.

--
Spider.
On high ground in SE London
gardening on heavy clay