IME, these types of spiraea (S. x bumalda) can be pruned hard and at just about any time of year you want to attempt it :-) I seriously disliked the pink flowers mine (Magic Carpet) produced and much preferred the foliage effect, so I pruned it back any time it produced flower buds - 3-4 times a season!! I also hard pruned it down to about 6 inches each fall to keep it dense and compact.

From time to time, you could get some dieback on individual branches. I wouldn't hesitate to remove them when you see them and let fresh growth fll in. This is a pretty indestructable shrub, all things considered :-)

I did the same to some this year in late winter. They are growing back quickly. Yes, there are still the stems visible in the center but I suspect that they will be covered in a few weeks. GG i, too, detest the bilious color of those flowers. When i am wandering around the garden with a cup of coffee or a glass of wine i pinch them off. I.m fighting a rearguard action!

I think that they look better pruned back harder, down to just a few inches. They regrow quickly as others have said.

LOL!! Sara, I have a thing about pink. No pink in my life and especially not in the garden. If I could find a spiraea like Magic Carpet or Limemound/Goldmound that never bloomed, I'd be a happy camper!! At least there are a few, like Ogon, that bloom white.

I love the S. thunbergiis, and the white flowers are definitely part of the attraction. I, too, am an anti-pinker. Especially that awful mauvey pink, such as the Spirea japonica flowers. I can abide a shell pink every now and again, such as 'Claire Matin' rose. Have you seen Spirea japonica 'White Gold'? It's not bad and has white flowers. I have one 'Magic Carpet' that is planted above a pony wall around the patio and I can sit on a chair and pluck at the flowers. Some seasons I am successful at obliterating all of the flowers on the side facing the patio. Then you walk around the back and it is solid pink!

My other pink shrub problem is Loropetalum. I love the purple leaves, detest the flowers. There is finally a purple-leaved, white flowering cultivar, 'Ruby Snow'.

Was pink forced on you pink haters as s child?

Yes, White Gold is lovely. As is S. betulifolia Glow Girl and Tor. They just don't have that new spring foliage coloraton that makes the bumaldas/japonicas so attractive. But they are not pink, so that's a good thing!!

Although I would not be inclined to plant one myself, I can tolerate pink flowered rhododendrons - good thing as otherwise, I couldn't leave the house in spring, as they are everywhere!!

My contractor and I were driving home from a job the other day and both of us commented on the pink dogwoods. Neither of us can understand why one would choose a pink dogwood over the incredibe beauty of a whie flowered one.

ETA: No kitasei........it is just such an insipid, anemic color that I have never cared for. Or it is that bilious Pepto Bismol pink that is even worse! Raspberry, coral or magenta are all fine......pink, no way!

When you prune this bush next, yank and rub the dead branches with a gloved hand to remove as much dead wood as you can. There may even be parts of the stump that are dead and should be broken off. Be brutal. The live branches will bend, not break.

Annual pruning of established Spiraea japonica down to short stubs at the end of winter is recommended.

Regarding them all being examples of Spiraea x bumalda instead:

http://apps.rhs.org.uk/horticulturaldatabase/summary2.asp?crit=bumalda&Genus=Spiraea

Remember the bit from Steel Magnolias where the mom (Sally Fields) said to the daughter (Julia Roberts) 'I have never seen anyone pick pink and pink for their wedding colors' and the daughter responds 'my colors are not pink and pink they are blush and bashful.' Well it's all pink to me!