I end up going to Harlequin's Gardens (in N Boulder, on a dirt road off Rte 36 near the Forest Service HQ) for a lot of supplies, particularly organic compost and fertilizers. They have an excellent selection of roses, a good selection of vegetables and herbs in the spring, and a kind of spotty, though high-quality, selection of everything else. (One bonus is that everything is pretty much guaranteed to do well here, which is not the case for many garden centers.) Somewhat expensive. Your best source for excellent advice on growing locally.

I go to Home Depot for landscaping materials, mulch and tools, though I avoid the bottom-end tools they sell, as they often don't survive their first encounter with Colorado clay.

I buy most of my seeds on-line, though some at McGuckin's. McGuckin's is also good for higher-quality tools, though somewhat pricey.

I've also bought plants from the Ute Trail Nursery's stand at the Boulder farmer's market; excellent plants, and their list of tomato varieties is enormous. Almost certainly worth a visit to Lyons, though I've not done so yet.

A few keys I've found to growing things in Boulder: either dig like crazy and add tons of acidic compost to the soil (which actually works very well), or make raised beds. Also, though it gets quite hot in the summer (at least for this New England boy), the nights are cold and the season relatively short (mid-May to early October, with very cold nights on either end, stunting growth), so expect to have a hard time with long-season or warm weather plants such as melons. (Doesn't stop me from trying!) Finally, drip irrigation is very helpful, esp. if you ever leave town. I bought the components for a two-zone setup on-line for perhaps $200 and it works beautifully all summer, with virtually zero attention.

Ian

On second thought, when I called Harlequin's "your best source for excellent advice on growing locally", I'd have to qualify it by saying that this site is definitely the first place I turn to. Despite the huge geographic range of the participants on this board - 1000+ miles north to south? - we're all dealing with bad soil, big temperature swings and low rainfall. A great resource.

I've had good luck at Sturtz & Copeland in Boulder, on Valmont between 28th and 30th. Decent selection and good quality. Paulino's Garden in Denver, a bit of a drive, has great selection and better prices.