Tuesday, February 14, 2012
Costus are my favourite plant.
Out of my 40 plus collection my favourite has to be Costus barbatus also known as comosus or more commonly as ‘Red Tower’.
Costus make for a bold tropical foliage effect in your garden and Comosus more so than most.
This Costus originates from Costa Rica and is for the most part cold tolerant but not of frost, perhaps in the really cold places it could be placed in a protected spot.
It will grow in full sun or shade but best in an understory location with filtered light.
It is not fussy about type of soil it will grow in.
The leaves when stroked underneath feel like the softest velvet, and no I do not have a fetish about this plant.
When in flower it has quite large red bracts with small yellow flowers protruding, these yellow flowers are edible and have a beautiful refreshing taste.
As with most Costus they are not affected by pests or disease.
This is the only Costus flower that actually tastes good; they are also very nice in a salad.
The red flower bract can last for up to six months.
It is easy to propagate.
When the stem has finished flowering cut the old flower head off and strip the fibrous matter from the stalk with a knife, then cut the stem into several pieces leaving at least three notches or segments showing, cut the bottom straight and the top at an angle, this is done so you know what part of the stem is top or bottom.
Place the cut stems in a pot using good quality potting mix, you can put several in one pot if you want or you can lay the stems flat in a foam box, the new shoots will appear on most of the notches.
You can just put the whole length of the stem under some compost and wait for the new shoots to appear; also you can just split the rhizome if you wish.
With the Asian type Costus known as Cheilocostus (Pink Shadow, Speciosus) the propagation is much easier as they throw off lateral shoots which can be cut off and planted straight into a pot.