By Rescue4legs
United States 
I planted 2 astilbes, one pink which briefly bloomed in color where as my red one has done no more than created a lot of green bush. My neighbor says to be patient however....still nothing.
My main concern is my pink Astilbe which flowers have now turned to a dry, burnt flower. Not sure if I need to prune, deadhead or what? Becoming quite frustrated. Not finding many direct answers online.
Hope someone can help.
Martine, PA
10 Jul, 2017
Answers
If these were only planted this year you just need patience. You should get flowers next year. No need to be concerned about either worry - its normal.
11 Jul, 2017
Astilbes prefer a damp environment ,or to be kept well watered..also they don't like full sun,so the flowers won't last very long...if you could replant them to a more shaded area,they will do much better next year..it's an easy plant to split,if you want to increase your stock...
11 Jul, 2017
welcome to GoY
I see you are in the USA so I don't know if you get winter frosts where you live. if you do get frosts the dead flower stems look wonderful in the frost. also sprayed silver/gold they look good in yuletide decorations.
I don't cut mine down as birds like the seeds also.
as said the other one will be bulking up ready to flower next year.
11 Jul, 2017
Some people like to use Astilbe seed heads in dried arrangements...and some don't! They do help feed the birds, so if you leave them on, the songbirds will thank you. Otherwise, deadhead them asap to encourage the plant to put energy into next year's growth and bloom.
10 Jul, 2017