We haven't been to the Garfield Park Conservatory Market Place, but from the sounds of it, we think it will be a great summer weekend destination. 
Besides the 10,000+ square foot garden center featuring seasonal bedding plants, perennials, shrubs, planting materials, hanging pots, the Conservatory's staff is always ready to offer gardening advice. Garfield Market calls itself "one of the city's best kept secrets," and we're looking forward to finding out why.
Also in the Market Place: Lady Lord Bath Essence, which sells all natural sea salts for whirlpools, tubs and jacuzzis, hand-made soaps, lotions, foot creams, gels and massage oils.
It's well worth the trip.
This is a great place any time of the year. I make a trip every January when it's bitter cold out. It's like a real cheap vascation to the tropics.