It's not free however; there are special times through out the year when they have free admission so you would have to check those with them. They used to have free admission the 1st Monday of the month, but I don't know if they still do. $10 for adults, $5 for children 4 -17 and 3 and under are free.
Worth the price, if you are into plants. Pretty special place.
50 dollars for a household for an annual membership
$10 I believe for basic entry
Its not free, it has a priced stated on there website.
Free
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