This is my first year planting spring flowering bulbs, which
grew nicely. I cut the dead flower and the stalk once it died back, and now the
foliage is yellow. What am I supposed to do with the yellow foliage? Pull it out? Cut it off? Just leave it alone? Also, will
planting some annual petunias now hurt the bulbs I have planted in the
garden? How close can I plant the petunia to the bulbs? I was going to
try and hide the yellow foliage.
The answer will depend on which bulbs you were growing. For example,
daffodil stems should not be cut back until at least 6 weeks after the
flowers have faded, and you should never tie the foliage in knots or
braid it (this is a common but ill-advised habit). You can leave
daffodils in the ground to naturalize and spread.
With tulips, you also need to wait at least 6 weeks from the fading of
the flowers before cutting back the leaves.
With hyacinths, you can pull away dead foliage and flower stems as they
fade. When the top growth has died down, you can either leave them in the
ground or dig up the bulbs, dry them off, and store them for replanting.
If you are growing iris, you can cut the dead flower stems to the base,
and cut away dead leaves in the summer. If they are bearded iris, the
fan of leaves may be cut back in the fall to about 8 inches above the
base.
(Source: The Plant Care Manual by Stefan Buczacki, Crown Publishers,
1993)
You can certainly plant your annual petunias quite close to bulbs like
daffodils and tulips and other bulbous plants which are quite vertical.
Just don’t plant right on top of the bulbs. To disguise dying bulb foliage, use perennial ground cover plants that keep their leaves over the winter, and that have stems soft enough for bulbs to emerge through them. Hardy geraniums (true geraniums, also called cranesbill) and creeping veronica, such as Veronica peduncularis ‘Georgia Blue,’ are good choices. You can remove dried leaves as needed, and they can be tidied or groomed in early spring.