Updated: Nov 13, 2022
To help prevent the delicate dandelion seed fluff from blowing away as you move it, a clear acrylic sealer spray (such as Krylon varnish sealer), can be sprayed gently on the dandelion carefully just before picking/cutting, then lightly spray again afterwards to capture any area that was missed.
Then let dry for a week or so depending on how big the stem is. Some resin artists said they only dried for a few days when not using the stem. Just be careful, because if it's not fully dehydrated, it can ruin your casting, if there is any moisture remaining in the dandelion stem.
Initially, after I picked some dandelions, I inserted a toothpick inside the stem, then set the dandelion stem with toothpick in a shooter glass, or styrofoam block to dry. The top may wilt over, but I was able to still set the dandelions into the mould, and the toothpick helped with stabilizing it, or it can be rested against the mold edge, or used to help suspend on some support piece, to hold the dandelion wish in place.
The bird in this photo has three dandelion puffs, babies breath and German statice, cast in iCoat TP24 FC casting epoxy (2:1 ratio).
The dandelion fluff on this piece was not sprayed with anything prior to casting. And the resin was poured over 3 sessions.
You can pour a bit of casting resin in your mould, then place dandelion wish inside, and gauge where about you'd like it to be set in the casting. Once that is determined, rest something (like a toothpick or skewer) across top of the mould, to use to suspend dandelion upside down, placed where you want it, so it is steady, and doesn't sink to the bottom of the mould.
Here is an example of a dandelion fluff that sank to the bottom of the mould, haha. It is still a very fun and cool casting, but I preferred the ones I made where it sat right in the middle of the mould. Since it was so light, I was asked if it would stay (in place) without suspending it, and now you can see that it does not. ;)
For reference, I had only poured resin about a third the way in to the mould on this one, then set dandelion in, then came back two days later, to add a next layer. I filled this mould in two layers, using the iCoat TP21.
Once resin is cured on that first layer, and dandelion wish is set in place, I cut the stem off (if not desired in piece), before pouring more resin in.
Pour resin on inside edge of mould, not on top of delicate dandelion wish. Resin will fill deep in and around the dandelionfluff on its own.
I learned recently that you can actually pick the dandelions closed. They take about a day to fully open ! Then leave for about a week, so the stems dry out.
Instead of using toothpicks, here is how I dried the dandelions the next time I picked some. On these ones I sprayed them first with Krylon acrylic sealer spray, prior to picking, and sprayed lightly again just after picking. Then hung them upside down to dehydrate fully.
Hope this is helpful information, for anyone who would like to try this fun casting project.