FL Slimcados prefer having their roots very wet. I soak them for 2-3 months before the stem - sometimes multiple stems - shows. By that point the roots are well developed. Depeding on the specific variant the true leaves spread when they are 12"-18" tall. Although, some with red stems wait until they are 24" tall. At that point they are ready to be planted in mucky swamp soil. This works for the Hass avacao, too. The trick is to be sure that you use fresh seeds that have never been dried, or, chilled in the refrigerator. Those will never grow. Also, I peel the papery cover from the seed. Those with a loose coat do better than ones harder to clean. I hope this helps.
Yes great info... I had never let it go for three months... Only about a week. Also used potting soil.. I'll try to use a different medium and soak em longer.. Thxs a bunch.