Earth Plaster Seams?

Hi all!
I’m currently applying an earth plaster to a straw bale studio and am having some issues getting the wet plaster to match up with areas that have already dried.  I’m wondering if anyone has any advice or a good trick to match it up without the seam showing.

Our mix is working great with no cracking or crumbling… it is roughy 1 earth, 1 sand, 3/4 chopped straw, 3/4 cellulose paper insulation, water as needed.

The problem I’m running into is that wherever I stop plastering for the day, the plaster dries to a certain extent (even when I cover it with a wet sheet and tarp).  When I come back to match the new plaster up to the older I get a discoloration at the seam.

Any help would be greatly appreciated!  I’ve scoured the internet and all the books I have and can’t find any info.

Thanks!
Kadin

Edit: some are better than others… you can kind of see them in this photo.  Also curious if anyone knows if there is a way to fix the ones I’ve already created.

My house had a similar situation, 3/4” basecoat with lots of seams. I followed up with an 1/8” finish coat of a finer mix and that solved that issue.

Scott Lawhead wrote:My house had a similar situation, 3/4” basecoat with lots of seams. I followed up with an 1/8” finish coat of a finer mix and that solved that issue.

When you did the 1/8” coat did you plaster the whole house at once?  Did you run into having seams anywhere in the 1/8” coat?

Yea, it was all at once. It was a big day with some help from friends. But it looks so much better! You could also do one seam above a door or window on the backside of the house. Corners are also possible seam areas as you can not really see both sides at the same time.

Sounds good.  Thanks.  Rounded corners so I’ll have to find a short spot above a window and do my best to blend the seam… or finish it in one go! 🙂

It looks beautiful! I encourage you to embrace the variations of natural materials. The pursuit of aesthetic purity tends to strip resilience and sustainability quite quickly.