Amaryllis bulbs can be full of surprises

Q. I’ve been astounded with the amaryllis bulb I acquired. It produced two sturdy stems, each stem bearing five enormous blooms. Have you ever heard of such a performance?

A. It is actually not unusual for an amaryllis bulb to produce two flower stems, especially from a newly purchased bulb. It is more usual for each stem to produce four blooms. Your bulb did deliver a bonus.

Q. Last fall I did not dig up my dahlia tubers because in my new garden at the coast I understood it was not necessary to dig and store dahlias for the winter. Now I’m wondering whether I made the right decision. How do you decide whether it is safe to leave them in the ground all year?

A. Because my soil is light, sand-based, quick to drain of excess moisture and not loaded with tuber-munching soil insects, I leave dahlia tubers in the ground. Whenever periods of extreme cold are predicted, I cover the tuber clump locations with soil from another part of the garden topped by a pile of leafy mulch.

This has not always worked well for me. The last time I added a few new beauties to my dahlia collection and left them in the ground along with several older clumps, a period of severe winter weather followed. All the new tubers froze, while the older, tougher varieties survived to grow and bloom.

Whether to dig up and store dahlia tubers or leave them where they grew depends on soil conditions, the dahlia variety, and the condition of the tubers. My pink cactus dahlia clumps, long-standing in the garden, were very mature, tough, and more resistant to challenging conditions than the more newly planted tubers.

That said, even the most resilient and enduring dahlia tuber clumps should be lifted every few years to divide and renew them. This allows for the removal of damaged, shrivelled or softened tubers in the clump and the division of very large clumps into a few pieces.