I noticed this spring that all of my kumquats and kumquat hybrids did not bloom in late March to early April as in years past. I was not sure why as we had a mild winter low of 25*, no damage and all were healthy. Now, in the last week all are flushing out a heavy set of bloom buds. We've had a fairly cool spring (for Dallas, TX) and now temps have been consistently in the 90's for a few weeks. I'm surprised that temps delayed the bloom set for that long- do you think this is what caused the delay?
thanks

If you have been getting kumquats to bloom in March and April--you are way ahead of us. Normal bloom time here is June and July--maybe a few by late May, but never in April.

Mine seem to bloom randomly. But generally between April to July. Sometimes I get some blooms in December to March if there are minor heat waves during that time.

Meiwas and Nagami are just now blooming. Destroyed the Chang Shou.
I am in SE Texas.

The lateness of your Kumquat's bloom is not surprising. My guess is that your Kumquat is also grafted onto a poncirus trifoliata root stock. Kumquat, itself, is a very hardy tree, and further, of all the stocks for citrus trees, trifoliate is the hardiest, and it imparts to the variety worked upon it some of its hardiness and its resistance to BOTH heat and cold. The resistance to heat is quite as important as the latter, for if the tree responds to heat by starting to grow and bloom, it becomes very tender. The measure of a variety's hardiness is frequently its RESISTANCE to higher temperatures by remaining dormant. Besides imparting to the cion (in this case the cion is also cold hardy) some of it ability to withstand cold, it has a tendency to retard growth in spring. It is also distinctly periodic in its growth, and it is not responsive to sudden changes of temperature during its dormant period, but responds gradually and slowly as the weather warms. - Millet (Drill ANWR)

Mine is on Trifoliate stock. My wife's parents have one that is not on Trifoliate-- I do not know what the rootstock is but it has relatively large single leaves.

I used to study drought tolerance of various plants and have some papers published during the late-80's. Mechanisms of drought and cold tolerances are strikingly similar or comparable. Going into "dormancy" OR growing very slow are only one of those similar mechanisms.

But take note that in the case of Poncirus, there is still another mechanism going on during the cold tolerance phase which is dissimilar to drought or hot tolerance, some cultivars defoliate or show tendencies to be deciduous during the onset of the cold season.

Joe, yes very true. Many of my FD stock loses all of most of their leaves over the winter. This cannot, of course, be observed when trifoliate is used as a root stock with another variety grafted upon it. The point you bring up between the similarities of drought and cold hardness is one that I had forgotten about. - Millet (Drill ANWR)

I purchased another kumquat from a florida company, it is now only starting show flowers. The one I have in the ground isnt flowering yet, then again I havent picked all the fruit.

question: Will the fruit on the tree retard the growth or delay the new blooms?
thanks

For my trees, they didn't seem to have any effect on bloom time at all.