The one at Rutger's Gardens is always Mother's Day Weekend. Here is the info. I don't know anything about the Middlesex County Extension Division, but would love to find out if anyone else knows.

http://ruevents.rutgers.edu/events/displayEvent.html?eventId=77949

There seems to be 2 participants in Rutgers Day Plant Sale: the Rutgers Master Gardeners of Middlesex County (who held their own follow-up plant sale on 5/3 at the 4-H Center in East Brunswick) and Rutgers Gardens who have their own Spring Flower Fair (they call it "The Ultimate Plant Sale") today (5/8/14) for Members Only from 3 -7:30 PM; Fri. 5/9/14 from 10 AM - 5 PM, Sat. 5/10/14 from 9:30 to 4 PM and Sun. 5/11/14 to 3 PM. This is at the Rutgers Gardens, at the Log Cabin in the gardens, 112 Ryders Lane, New Brunswick.Their sale always takes place on Mother's Day weekend. Their website (http://rutgersgardens.rutgers.edu/directions.html) advises: "Please note that if you are using either a GPS or on line mapping service the directions may be wrong if you use our Ryders Lane address. Please use Log Cabin Road, New Brunswick as the address."

The Rutgers Master Gardeners of Monmouth County have a plant sale at the Monmouth County agricultural building, 4000 Kozloski Road, Freehold Township, May 16 from 9 a.m. to 5 p.m. and May 17 from 9 a.m. to 3 p.m., rain or shine.

I believe the Deep Cut Gardens in Middletown has their Spring Perennial Plant Swap in April, and a fall one, as well. They are part of the Monmouth County Park System, at 152 Red Hill Rd. You bring a plant and get to swap for an equal-sized plant.

This post was edited by wannaknow1 on Thu, May 8, 14 at 13:39