Between the two of my small satsuma trees there was ONE flower this Spring. That has started turning into a fruit, but meanwhile there seems to be no indication of other flowers to come.

Last fall I got about 40+ fruit off each tree, and the year before pretty close to that amount. Do these things take a year off sometimes or what might have caused this?

That's pretty normal until they get some size to them.

Me too

In citrus, alternate bearing of mandarins, including satsumas, is a recognized problem throughout the world. Alternate bearing also occurs in many mid-season seedy orange varieties. Factors which may perpetuate alternate bearing include excessive crop load, and its associated stress on the tree. The heavy crop load on the "on-year"causes a severe depletion of carbohydrate reserves, particularly starch. The large number of fruits during the on-year competes for carbohydrates and reduces the amount of vegetative growth, which is the primary source of flowering the subsequent year. There are a number of practices to control alternate bearing. The most successful include reduceing flowering during the on-year, and or, fruit thinning during the on-year to reduce the crop load. - Millet

Thanks Millet, that was a simple clear answer.

They did seem to have many more fruit than I thought trees that size would support last year.

I have two Taroccos, both the same age, graft, size, container & medium, side by side, fertilizer, mulch, watering schedule. everything! They are not that large either about 5 feet tall by 4 feet wide. The only difference is one decided to hold about twice an many fruit this year, one has about 20 one has about 10. The one with 10 looks worlds better putting on new growth the fruit are a good size, distributed across the canopy evenly. overall the tree looks very healthy. The one with 20 has much smaller fruit, no new growth, not as healthy looking or as dark green, showing some alight deficiency. I notice more leaf spotting and more bugs too.

One challenge is knowing how much thinning to do, I guess you just have to know your trees.

I have noticed this week that the trees are suddenly showing new leaf and branch growth.

A citrus fruit only uses the energy produced by the 3 or 4 closest leaves to set, grow and finally mature. Therefore, one common method of fruit thinning is to remove excess fruit, leaving one fruit for each 3 or 4 leaves. This will produce larger size fruit, and reduce alternate bearing in the following year. - Millet