Question
I sent away for arborvitae seeds.  Put them in Jiffy Mix in refrigerator for 60 days to germinate.  what steps do I need to take now to have success?

Answer
First of all the seeds must undergo stratification (a process whereby the seeds are placed into an environment that creates a false winter). This is usually done by putting the seeds into a plastic back filled with moist soil and then placing the bag inside a refrigerator. This is what I think you have done.

Seed - best sown when ripe in the autumn in a cold frame. Stored seed germinates best if given a short cold stratification. It can be sown in a cold frame in late winter. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts.

If growing large quantities of plants, the seed can be sown in an outdoor seed bed in mid spring. Grow the plants on for two years and then plant them out into their permanent positions in late autumn or early spring.