So have you observed any russet mites on your plants?
They are insidious and difficult to control. I have one plant (Variegated Cherokee Purple) that I am trying to basically scrub clean of all inhabitants to see what happens, but the ladybugs -despite obvious piggyback rides- I think are finding the house temp to be too low. However, I HAVE seen one and two (meaning very small number of) larval forms that have grown into adults from the previously released group (different species) so it's not entirely impossible it seems. I'm considering getting green lacewings or predatory mites now.
Since last posting, I have given up on a handful of plants and put them outside to freeze off. (I actually sowed some halesia (silverbell) tree seeds in those pots to see if they will cold stratefy and sprout later
-- no biggie if they don't. ). I'm also attempting to keep alive two indeterminate varieties by rooting cuttings.
It's snowing outside now -since overnight and still- and accumulation on the patio table looks like 6 inches or more. Temp in the 20's. (sigh)
But really, this -mid March- is typically the most difficult period of the winter indoor growing every year. Stressed from low humidity, low temp, occasional overwatering, and the usual indoor gardening pests like mites and aphids, scale insects, fungus gnats.... Too freezing cold to let anything out except on day to day basis -- which for me with so many plants is near impossible to manage for all. So only the select few gets the VIP shuttle ride treatment. If you only have a small number of plants, I think it's worth doing.
This Jackass Yellow took all winter to produce a single ripening fruit, albeit a big one. Due to nature of gradual pollen set in a mega/fused bloom, it is already ripe on the far side while the near side lobes are still hard and green/barely color breaking. Unless growing for giant tomatoes, this kind of characteristic is actually undesirable.
-- no doubt this is why the breeder of this variety is now selecting for single blossom fruit characteristic. It's a dwarf plant growing only to about 4 feet tall. If it had been provided with much more favorable growing conditions -- full exposure supplemental light (instead of one sided vertical twin 4' t-12) warmer (70's instead of 60's/50's) and in larger container (5 gal bucket instead of a measly 6-1/2" pot) -- I would think it would have produced more and likely earlier.