Book Review: Peonies by Claire Austin
A new respect for elders

Lavatera is lost - but not Coleus

Malva (left) and Lavatera - both now Malva.
Malva (left) and Lavatera - both are now Malva.

The latest issue of the RHS magazine The Plant Review arrived recently – always a treat – and tucked away in what they call Classification Corner is the news that the genus Lavatera no longer exists – it’s been amalgamated into Malva.

Now most of us, taking a look at a Lavatera (above right) and at a Malva (above left), would wonder why they were separated in the first place. Needless to say, it’s all down to our old friend Carl Linnaeus, way back in 1753, and what Royal Horticultural Society botanist Dawn Edwards refers to as “differences in epicalyx segment fusion”.

Yes, but what on earth is the epicalyx? Well, the green calyx encloses the petals in bud, and the epicalyx refers to the little green bits that are outside the base of the calyx. Linnaeus thought that whether or not these little bits were fused together at the base (in Lavatera) or not fused at the base (as in Malva) was important.

It wasn’t long before botanists decided that Linnaeus had probably got it wrong but no one did anything about it until relatively recently. Back in 1998 molecular studies revealed that this division did not reflect the true relationship between the species grouped under Lavatera and those grouped under Malva. So, after careful deliberation – and they always deliberate long and hard these days, the RHS and botanists around the word agree - they’re all Malva.

I have to say: I can’t really disagree. And as they’re less separate than we thought, perhaps someone should try crossing them together…. Could be interesting.

• I should mention that it’s also been decided that Coleus are, indeed, Coleus. Not Solenostemon. Or Plectranthus. Which is good news all round.

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