Q. What can I safely plant outdoors even though our last average frost date is still almost two months away?
A. This is the perfect time to start working on your cool-season crops. First, you need to know your average last-frost-of-the-season date. Then count backward to know when you can safely sow various vegetable seeds in your area.
Here are general guidelines:
Very hardy vegetables: Sow seeds for spinach, turnips, peas and collards four to six weeks before the frost-free date. That's when you can also plant potato tubers, onion sets, broccoli transplants and asparagus crowns.
Frost-tolerant vegetables: Sow seeds for carrots, radishes, beets and mustard plants two to three weeks before the frost-free date. Put in cauliflower transplants. These crops can tolerate light frosts but are a little more cold-sensitive than the first group.
Keep in mind that frost dates are only approximations. In any given year, the last frost can hit earlier or later, depending on the whims of the weather. And your yard can present a microclimate that's even considerably different than your local average frost date. When a cold snap hits, cover your crops.
As for woody shrubs and trees, you can plant those any time that the ground isn't frozen (or too wet to work).
Good luck and happy gardening!