What to do with bulbs that don't have flowers.
Rodger Whitlock (Wed, 13 Apr 2016 12:15:24 PDT)

On 13 Apr 2016, at 12:26, Sujit Hart wrote:

That implies that the bulbs haven't been attacked by diseases, so the answer
must lie in the environment, primarily soil and/or climate.

In that case, I suggest two tactics:

1. Fertilize. Theoretically, you'd want a fertilizer relatively low in
nitrogen, but a light sprinklng of not-too-much general purpose granular
fertilizer will do. Even an application in late summer or early fall (e.g.
Labor Day Weekend) may give results. Narcissus 'Jack Snipe', for example,
flowered after years of non-flowering when given a little 13-16-10 around Labor
Day.

This surprised me because narcissus supposedly form next spring's flowers
primordia during the summer.

2. Move the bulbs to a north-facing site with winter shade from a wall to give
the bulbs more winter chill.

Lifting the bulbs and storing them dry after the foliage dies until you replant
them in the fall may also help, by protecting them from excessive summer wet.

One other point about tulips that may be of general interest: You sometimes see
gardening writers confuse "needs a dry summer" with "likes a sandy soil." The
difficulty with this simple-minded idiocy is that many bulbs prefer a rather
rich, heavy soil and sandy soils are too lean to feed them adequately. Many
Central Asian tulips grow natively in heavy gumbo clay.

If your soil is sandy and lean, the situation may be a lost cause. Sandy soils
don't retain soluble nutrients well.

PS: "Not-too-much" fertilizer means just a few ounces per square yard.
--
Rodger Whitlock
Victoria, British Columbia, Canada
Z. 7-8, cool Mediterranean climate