There are a few reasons why your plants are showing yet. The weather was cold in many areas this winter.
Cold weather can delay the start of spring plant activity.
Bulbs have to warm up, so if the ground is too cold, they may still be snuggled up for the winter. It may be too early. If you're like me, you're dying to see the first evidence of spring. Well, check your garden journal. If you're keeping records, you can tell if it's too early.