Hmmm. My mom used to change the water every couple of days or so as it would start to smell yucky. We never had 100% rate with starting the pits, some would never sprout.

You can also try rooting the pit by shoving it, fat side down, into a pot of soil. Have about an 1/5" of the upper pit above the soil surface. Keep the soil moist but not soggy.

T

Yep - Trudi is right - it rotted. That happens a lot. Throw it away & start over in the soil just as she explains. It will grow into a stronger plant. Have fun!

sometimes it may take over 6 months to germinate a seed in water, I have been doing avacadoes every year for over 10 years now. Keep changing and adding new water, make sure at least half the seed is in water or better yer use the trudi and DurtyKneez method...remember to have lots of patience and dont give up....6 months or longer up to one year to get roots and a shoot to come on for me in Maine!
I have many trees now in pots that go inside for the winters. I have different store varities too. MOst all my fruits were grown organicly, that may have some bearing too.