The viability of haworthia seeds start decreasing after about 1 year. I strive to sell fresh seeds only and will always indicate the time of harvesting in the individual listing.
Seeds increasing in age will be marked down in the store.
Due to the many factors involved, no guarantees can be provided as to the viability and germination rates of the seeds sold and no refund will be offered. In my opinion, a germination rate between of 50% and above is a reasonable expectation for haworthia seeds.
However, if you experience particularly bad germination with a certain hybrid and can provide evidence that other seeds under the exact same circumstances have performed very well, I will gladly replace with something of similar value in a future order. I also always sow some of each hybrid as well, and will also compare with my own results.