Fertilizer mixing criteria during seasons

[jrguevar]

Hello to all,
As how the title says I've been thinking lately on how some people have different inorganic fertilizer mixtures made according to the season.
This year I wanted to try it, I believe I have read that *In general* (sometimes hate their is nothing general with orchids...) if you see new sprouts you are better off giving a fert with more nitogren in it (indeed without over passing amounts such as 30-30-30) and even better if you manage low and constant concentrations such as 1gr/lt (yes, not the same if you are fert a catasetum vrs an epidendrum or vrs a cattleya...).

Now if you start seeing a flower spike than you have to switch to a more potassium or phosphorous mixture (5-15-30 for example) to avoid flower abortions and to have more durable flowers *In general plants, not only orchids*. I live in a place where you can only determine roughly summer from winter in the tropic so I prefer to work accordingly on what stage the plant is (giving roots, giving sprouts, giving flowers) Both statements seem feasible and reasonable, so now comes my real question here;
What do growers recommend if you have at the same time a flower spike growing along with some new sprouts? like if you have a large plant which can give flower spikes by one side and sprouts from another, what would you do use both fertilizers in each half, no idea, just writing nonsense here at the end... so I would like to here everyone's opinion on it,

[Ray]

I am a big proponent of looking at what is happening to plants dealing with Mother Nature....

Epiphytic orchids get fed when it rains, and that consists of the dust, animal droppings, and exudates washed down from the canopy above. In general, analyses of such "throughfall" and "trunk flow" tend to be frequent, VERY dilute (max of 15-25 ppm total dissolved solids), quite consistent year-round, and almost all nitrogen.

Also, if you look at the chemical makeup of an orchid, outside of the 95% of it that's water, 95% of the remainder is carbon, oxygen, hydrogen and nitrogen. The first three come from air and water, the N is from fertilizer.

That tells me that changing formulas isn't necessary or even beneficial, that I should feed frequently and dilutely, and that nitrogen management isn't a matter of fertilizer formula ratios, but of concentration. I have used K-Lite (12-1-1-10 Ca-3Mg) consistently for 5 years now at about 25 ppm N, and have seen nothing but tremendous growth and flowering.

You can overdo the nitrogen with the 5-15-30 by overusing it, or you cannot do so with the 30-30-30 by controlling your application.

You are correct that a plant in active growth will need more fertilizer than it will when paused, building up stores, but even then the demand is not all that much; in order to gain one pound of mass (a lot for most orchids), it must absorb and process about 25 gallons of water, but only about a teaspoon of NPK fertilizer ingredients.

I'll get off of my soapbox after one, final comment: fertilizer is probably the least important of all orchid culture parameters. Focus on the others, and periodically give them "some" food, and they'll perform well for you. Feeding NEVER compensates for failings in other areas.