Water hawthorn overwinters for me here but it gets off to a pretty slow start in the spring. I drop its pot into the 4' section of the pond to keep it through the winter. I think it is on the edge of its hardiness zone here.
I collect the large seed pods when they are very fat and almost ready to burst. The seeds are easily germinated in a jar of water in a sunny window sill. Germination is excellent, have to be careful potting them up. After several tries and much error I now just put some soil in a pot when they get to be of handle-able size, fill partially with water and float the seedlings. As long as the water isn't too deep they seem to root easily into the soil on their own. Then I gradually top up the water (or gradually move the pot into a progressively deeper part of the pond) until they are big enough to go into the position I want. I've given lots of these away.
This is a picture of newly germinated water hawthorn seedlings from my first attempt; toothpick on top shows scale:
![](http://img.photobucket.com/albums/v257/emm11/waterhawthornseedlingJun05.jpg)
Love your pink blooms Annette. Mine are white.
![](http://img.photobucket.com/albums/v257/emm11/OutdoorAdventureSkillsPlus064.jpg)
The blooms are very fragrant, almost like vanilla. In my pond they bloom early in the summer and then the leaves fade away; just a few small ones remaining through the summer. When the temperatures cool later in the summer they resume blooming.
emm