Quote:
"Even if you find an unplanted sack of tulips or daffodils in January or February, plant them and take your chances. No matter what, they're better off giving it a fighting chance in the ground or a chilled pot than wasting away in the garage or cupboard. Flower bulbs are survivors by nature's design. Every year stories abound of bulbs that bloom after being planted under the most improbable circumstances"
Source:
http://www.hgtv.com/design/outdoor-design/landscaping-and-hardscaping/qa-when-is-it-too-late-to-plant-bulbs
A further point is that many sources suggest autumn planting simply because it's "before the first frost". Given the incredibly mild weather we've been experiencing, it will still be before the first frost in many parts of the country anyway. (Obviously though, you'll probably have a much better chance of success if you live in Truro, rather than Thurso!)