While the greenhouse part of this is disappointing, the Swiftpro growing station is amazing
As Saltypaws first pointed out, using sunlight in your composter will weed your plants. This almost makes up for the greenhouse not working. It also does spawn seeds and things grow very fast.
If you place the big greenhouse, it spawns gobs of seeds. There are numerous sunflowers there, so you can gather plenty of sunlight. It sells for $100 each which isn't too shabby for a struggling sim.
If they get the greenhouse thing worked out, I'll be a happy gardener.