Dendrobium NoID growth took off after adding fertilizer to my regimen

[FL_Orchid_Collector]

I've been growing these for about three years, they've been in the same location with the same care the entire time. Northern-exposed screened area, dappled light morning and evening, no direct sun around mid-day. Extreme low temps in the mid 30s, extreme highs mid 90s. Humidity 40-90% at the extremes, with Spring being the least humid season with an average of 72%.

I've believed some advice I've heard over the years, that orchids don't need fertilizer. I don't know why it sounded good but the plants didn't die, and some of the Phals were reblooming in spring so it was working, right?

I finally decided about six weeks ago to finally buckle and start fertilizing in an attempt to get things moving with the Dens., Rhy., and two Phals. which never had quite enough roots and didn't grow new leaves last year or this year.

I began applying fertilizer at full strength once a week (I know, you should go easy at first, or always, but I want results and I'm sure as much as the manufacturer wants to sell more fertilizer they also don't want people to damage their orchids, so I just went with it), and that first day some of the Dens. root tips burned. I thought I would probably quit using it, it just didn't seem worth the risk. Two days later though, BAM! The new canes started blasting out roots twice as thick as before, with longer tips and they grow twice as fast. The new canes this year are growing faster and with more and broader leaves. I was going to put some arrows or circles to point out the new growths but looking at the pics I realize it's so obvious it's not even necessary. There a detail showing a new root alongside one of the previous roots so any perspective illusion is eliminated. The Rhy. and Phals. have also improved dramatically but there's not an obvious before/after I can show. The roots are growing much faster and they're branching more but they didn't get any thicker. The Rhy. went from one growing root tip to at least 9.