Will you be keeping the daffs there after the construction? If it were me I'd probably dig them and replant immediately somewhere else. Mark the spot, dig them up this fall, replant back where they were.

Ideally though, daffs are better in less formal areas, where the foliage can wither without being obvious, as they would be next to the house foundation. A lot of people plant daylillies next to them, so their foliage can help hide the decaying daff foliage.

Because the daffs are undoubtedly in close proximity to each other it might be difficult to measure out just where each bulb is so it can be moved with any size of root ball.
With the disturbance, they will probably wilt when first seeing the light of day.

The workmen putting the plastic across the area know it is for a purpose and might such cover be removable when work above it poses no danger to what's underneath.
For sure, the sun beating down on the plastic will increase the temperature under it---I take it you're in Oregon and is the April sun in your area so dreadful at this time of season and might the plants under the plastic be safe for a little while while work is proceeding over them.

It would be difficult to transplnat en masse a bed without something unforeseen happening.
If you can sight each bulb, how about potting them up in containers and keeping them there until you can put 'em back where they were.

It's actually just one clump of daffodils. Eventually I do want to move them because they're a beautiful old creamy white jonquily-looking type that came with the house. They've probably been there 10 or 20 years. I think I'll pot them up and then re-site them when I have a place. Hopefully if I dig up the whole big clump in a scoop or two, they will survive in pots in the shade for a couple of weeks. Thanks for the advice!

Hi Oregongirlie,

I rescued some daffodils just as they were coming into bloom by digging up the entire clump. They still bloomed and are looking quite healthy. Once the foliage dies back, I will plant them in the ground as individual bulbs.

Kathy

Hi Oregongirlie,

Would you mind contacting me? No worries -- it's all good. You can either click on the link below or email me thru my profile.
Thanks!

Tamara Amey
GardenWeb Community Manager