It depends on how hot the compost is, and what type of compost. If it has been aged for several years, you could go with 50%.

I don't remember all the ins and outs, as in what manure works best or which to watch out for, but if it is fresh compost, it can act as poison to your plants, or literally get too hot and burn the plant roots. One sage grower uses pea or bean seed to test new compost before planting out. You might ask for a cup of both, do the pea test, and make your decision based on that.

Thank you for the advise. I know the farm ages their compost for 9-12 months. I'm going to get some samples today and I think I'll try the seed test you mention.

Be sure to ask what the compost is made from. Then, you can do a bit of research on it so you can make a more informed decision. Leaf compost is different then cow compost.