Iris lazica
Rodger Whitlock (Thu, 09 Feb 2012 08:02:10 PST)

On 8 Feb 2012, at 16:54, Jane McGary wrote:

Speaking of irises, last fall I bought some Pacific Coast hybrid
irises that were shipped to me bare-root. I planted them in a
well-drained spot the day they arrived, but the majority of them have
failed to grow. Never again!

Last fall, the municipality reconstructed a big storm sewer running right
across my front garden. This involved excavating a trench at least 12' wide and
up in places 10' deep. (Yes, it was a horror show. If I had deep pockets and a
litigious nature, I'd sue.)

Among the plants I salvaged was a large clump of Iris thompsonii. In the
process of extricating it from the ground, numerous fragments broke off. I
dibbled the ones with a growing point into a deep flat, gave it a good
watering, put it under cover out of the rain, and have left it alone.

It appears that the vast majority of these little divisions have established,
but I'll leave them in the flat for another year so their root systems have
time to develop.

I did much the same with Iris unguicularis, but in that case, simply tucked the
divisions into the soil of my I.u. bed. Those also seem to be establishing
nicely.

In both cases I cut the foliage back to just a few mm long.

Moral: summer-dormant rhizomatous irises can be divided successfully in the
fall and will establish if the divisions are ***immediately*** replanted.

In Jane's shoes, I'd check to see if the rhizomes are still sound. If so, be
patient. They may not start to grow until this coming fall.
--
Rodger Whitlock
Victoria, British Columbia, Canada
Z. 7-8, cool Mediterranean climate