Enterprise Farm CSA
I'm a member of their winter CSA, and have signed up to continue for the summer/fall. The winter CSA was quite a good variety through mid-March: winter squash, potatoes, onions, garlic, parsnips, sweet potatoes, leafy greens, beets, carrots, apples (a mix of local storage crops and produce from East coast farms further south Enterprise has relationships with); and cherry tomatoes, summer squash, and eggplant from farms they have connections with in Florida. Lately it has been a bit on the sparse side, as all the local storage veggies are gone and the spring veggies are just starting to come in; but of course no year round CSA would be able to provide much variety in late March and April.
Based on my experience with the winter CSA, I expect the summer one to be quite good, and would recommend it. I shopped at their stand at the Davis Square farmer's market a lot last summer and found Enterprise to be consistently have some of the best variety of produce.
As far as quantity goes: my wife and I split a large share with another couple, and it is more than enough. We generally cook vegetarian dinners 4-5 times a week, and find that we rarely need to supplemental the veggies from the CSA with produce from the grocery store. For 1-2 people, a small share is probably plenty (depending on your cooking habits), although if you can find enough people to split it with, I think the larger share has more variety and is a better deal.
I've been doing their summer CSA, picking up at the farm in Western Massachusetts, and haven't been very happy with it. In Boston, I'd recommend looking into a share with Drumlin Farm, I used to get their CSA and liked it a lot. Red Fire Farm is also one I would recommend before Enterprise.
I can't, obviously, speak to their Boston shares, but the one I get out here has just not been that great. Produce quality has not been impressive - for example, this weeks tomatoes (end of summer, should be perfect) are rock hard, the kind of thing I would not buy in a store in January. They have had ongoing problems with salad mix greens not being washed well, and being gritty, and have not resolved this problem even after I spoke with them about it. I've done a lot of CSA's in a lot of different towns and just have not been very impressed with this one.
This has been a really hard year for CSAs (and farms in general), so I wouldn't necessarily judge a bad experience this year against previous years. A lot of CSAs had no tomatoes at all, and at least one had to completely stop distribution for several weeks. Simply managing to provide tomatoes (especially organic tomatoes) at all is a major accomplishment, given the season.
Even at farmer's markets produce quality has been lower than last year -- bell peppers haven't been looking great, squash was much less abundant than in the past, and tomatoes obviously were and are very scarce.
I'm doing Enterprise's CSA this year and completely love it. Because they have arrangements with other farms where they supplement what they grow with produce from other farms, you get a ton more variety than other CSAs. Also, their season is longer because of it. For example, this spring, while Mass farms still had only root vegetables and some greens, we got blueberries and some amazing strawberries.
Not sure if I understand your problem with the greens. Greens from a farm will have some dirt/grit on them; they need to be washed before you eat them.
The tomatoes haven't been great this year, but I think they've done better than most CSAs.
And, overall, I've been very, very happy with what I've gotten from them, especially compared to other farms. I'll definitely re-up when the season ends.
I'm glad other folks are happy - makes me wonder if there is a difference between Boston shares and ones out west.
Re: the greens, I'm not talking about kale or chard or spinach or heads of lettuce, I'm talking about bagged salad mix - baby arugula, baby lettuces, etc. My experience is the standard for those is that they are washed and spun before they are bagged, and thus not dirty or gritty. That is the case when I buy greens at the farmer's market, has been the case with every other CSA I've done (maybe 10 different farms) but has not with Enterprise.
Anyhow, I really like the model they work with, i.e extended season, trading for or buying produce within the local foodshed, etc. I've just not been very impressed with what I've seen in practice, and have been jealously eyeing friends CSA's from other farms.