Fremontodendron mexicanum germination success with hot water and sand paper treatments
Our seedbank made a mini breakthrough this week with a new pretreatment for our germination trials of Fremontodendron mexicanum. After an initial trial that consisted of only imbibing yielded only a few germinants, we tried two treatments to weaken the seed coat: hot water and scratching the coat with sand paper. Both treatments dramatically increased germination.
I have also had good success with hot water. My treatment was with nearly boiling water which was a little nerve wracking given I had a small seed sample. Would I kill the seed?! It worked with 8 of 10 germinating within 10 days. Not sure I needed to go that hot. What was the temp you used?
The hot water temp was just boiled at 190F but immediately started to cool. The seed was imbibed for 24hrs. The hot water treatment yielded more consistent results and grew less mold than compared to the seeds that were only sanded down. Also, two people sanded the seed coats and a few seeds had to be re-sanded as some of the seeds didn’t show signs of imbibition so consistency in sanding really mattered. Germination was excellent with both treatments.