Iris Rhizomes

ciaranmcgrenera

I bought some Iris Rhizomes sold alongside summer flowering bulbs like Gladiolus etc a while back- they were sold as “summer bulbs” effectively, but am I right in saying that those Rhizomes won’t flower this year- instead they’ll store energy to flower next year?

Inglezinho

German Irises (Iris germanica) usually flower mid to late May in most parts of the country. You will soon know ! I'm not sure I would describe May as "summer". Certainly April isn't...Good luck!

ciaranmcgrenera

Inglezinho said:

German Irises (Iris germanica) usually flower mid to late May in most parts of the country. You will soon know ! I'm not sure I would describe May as "summer". Certainly April isn't...Good luck!

Thanks! I was late to get started and only just planted today so if they flower at all it’ll be late I’d say. 

KeenOnGreen

@ciaranmcgrenera Make sure you plant them with the rhizomes fully exposed on the surface of the soil, so that they get full exposure to the sun.  They need as much sun as possible each day, so avoid any other plants shading them if you can.

If they have any old/dead leaves now, cut then off to about a few inches off the ground.  Give them a liquid feed every week or two, starting now, and going on after they have flowered.  With any luck you may get some flowers this year.

We remove the seed heads after flowering, to encourage them to put their energy into the rhizome, to make more flowers for next year.  They can need staking when they are newly planted, especially when they are in full leaf/flower.  We use u-shaped metal weed membrane pins, they hold the rhizomes nicely into the ground.

ciaranmcgrenera

Thanks very much! They must grow very quickly!

How do they deal with frosts?