This hasn't happened to me in recent years, but long ago I ordered asparagus crowns, which of course came weeks before I had their bed ready. Long ago I vowed to never again let that happen. Even the gardener determined to only plant one of the supermale cultivars will find if they diligently barter that supermale asparagus does indeed set seed. The amount of time you gain is negligable in buying crowns. Start seed in a shallow pan and start on your bed at your leisure. Baby seedling 'grass is tiny, but you'll be planting them to field where they won't need to be moved again. Plus you'll be in much better humor as you plant
I grew some Asparagus from seed. It grew, but it was tiny and very hard to weed around. It took almost 3 years before it was big enough to fend for itself, and another 2 years before I could harvest any. Unless you are very patient, I would definitely recommend starting with crowns!
We started with 1 year crowns, and have a lovely asparagus bed. In fact, I recently posted about cutting the first asparagus of the season. Here in Texas we get two harvests each year--spring and fall, with the fall harvest being smaller. Unless you are starting a very large asparagus bed, or are very frugal, starting from seed is a waste of time for the home gardener. I would suggest starting with crowns and if you want to expand, then considering seed.
