I use generic 20-20-20 all year round on all my plants at quarter strength. I would go crazy trying to customize by season with the different plants I have.

Also, IMO most of fertilizer is wasted. Orchids are very slow growing most of the year and take only some of the fertilizer offered to them.

Ditch the bloom formula and go for the 20-10-20; your plants need more nitrogen than anything else. These numbers are a little on the high side for my taste. I use dynagro formula and the numbers are something along the lines of 9-7-8 (don't have my bottle in front of me, but the numbers are very close). You don't need as heavy a formula with orchids as you do with other plants. Keep in mind though that when winter hits, you shouldn't be fertilizing your plants because their growth is severly retarded, and any fertilizer used on a non growing plant is wasted fertilizer.

I would skip the pellets unless you have a very fine mixture. If you use them in coarse bark mix, they will indeed most likely drain out long before they break down enough to release their nutrients. Somthing more fine, like say a peat mixture for phrags or terrestrials, is more suited for pellet use.

I can't tell you much about the b-vitamins. the idea has been bandied around before. However, I would wonder if the tablets you get in the store are an absorbable form for plants. I.E. plants take up NH4+ nitrogen form much better than NO3- form (this specific example could be inaccurate, i'm not up on my nitrification cycle, but the prinicple is the same that forms of a nutrient are more usable than others).

Good luck!

I forgot to mention that I dilute the dose.

Since there are so many different kind of fertilizers out there, can you recommend one? I know I need to feed my orchids. I haven't used one in a long while!

I'd say there are two that most people pine for. Dynagro makes a really nice product. MSU ferts are really good too, with different formulas depending on if you're using tap water or distilled water.

I use tap water for most of my orchids and distilled water for my masdies. Now I know what to look for online and/or at the store. Thanks for that info, terpguy!

Superthrive, Shultz's vitamin B formula and Dyna-Grow KLN do pretty much the same thing and are used mainly to encourage root growth. If these are used near the time when spiking or blooming is desired, they may hinder the process as they will be telling the plant the opposite. In fact, it says so on all the Dyna-Grow KLN literature.

Hi, ms minnamouse's SuperThrive Growmore Bloom Formula 6-30-30 sounds like it would be good for my dendrobium kingianum. I have been trying to find, without success so far, something in 9-30-25 for my den. king, which is the ratio recommended for them. Anybody know of a commercial one in that formula?

The Superthrive and Growmore Bloom Formula are two separate products. I believe Growmore has their own site.

I wouldn't suggest using the 6-30-30. Nitrogen (the first number) is the most essential to your plants. You'd be overburdening them with less useful nutrients and not giving them enough of what they need. And i'd hypothesize that with that heavy of formula, you might see quicker-than-usual salt buildup in your pot. If you're trying to reduce nitrogen, the best way to do it is simply to not fertilize at all.

I'm curious as to why bloom or bust would even think about using 6-30-30 on Den. kigianum an orchid that gets by on next to nothing in the wild.

Any problems in blooming said orchid are best solved by setting conditions to its liking rather than applying an expensive boutique fertilizer.

I see the old urea free urban myth still persists. Will it ever die.

Hi,
This is the first year I am growing 2 phrags. What kind of fertilizer, and how much, do you use on these orchids?

Mine sit in a saucer of water. Rainwater in the winter and well water during the rest of the year.

Also, do you water/fertilize these plants on top or only from the bottom?

Thanks.

Arthurm, in nature pretty much ALL orchids get by on next to nothing, don't they? That does not mean, however, that I want my plants to just "get by".

They will grow with little feeding, but all will grow better with more - up to a limit, of course.

Addressing some of the other comments, nitrogen is important, but too much nitrogen is bad for blooming, and leads to weak vegetative growth. Anything more than a few percent phosphorus is wasted. The plant cannot use it, so simply doesn't, so it ends up being dumped in the ground or in ponds where it can lead to eutrification.

I'm a firm believer in Dyna-Gro "Grow" formula and the original GreenCare MSU formulas. They are complete with macro-, minor-, and trace elements, have formulas balanced well for a varied collection of plants, and if used at moderate levels (I target 125 ppm N - divide 10 by the %N in the formula to get teaspoons per gallon), creates little, if any mineral buildup issues.

The only way to initiate blooming is through light level, and for most of us, that means more light. There is no fertilizer that causes flowers to form.

Fertilizer can make a difference in the number and size of flowers, but even then it is the fertilizing throughout the year that makes a difference, not at blooming time.

Urea myth? Why isn't urea bad?

Urea breaks down to ammonia and carbon dioxide pretty quickly. For a slow growing plant like an orchid most of the value is lost because the plant doesn't use it quickly.

It is great for fast growing plants. Nothing greens up a lawn better than a good dose of urea.

Minnamouse. Where did you get the idea that Urea was bad? Just looking at my can of "orchid food with trace elements" it says,
Total Nitrogen 12.2%
N as Nitrate Form 4.3%
N as Ammonium Form 3.9%
N as Urea 4.0%
This "orchid Food" was purchased from a supplier who sells lots of this stuff to orchid growers around this country.

Now look at the picture in the link. This is part of the collection of a specialist grower of Softcane/Nobile type Dendrobiums. In Summer only those orchids are fertilized using Miracle-Gro all purpose plant food which of course contains Urea.

Re, the kingianum, of course orchids get by on next to nothing in nature. It is just that Den. kingianum gets by on less than less.... and the poster is proposing to fertilize with a fertilizer that to me seems to have a rather strange NPK ratio.

Here is a link that might be useful: Part of a Soft cane collection in bloom

Hi Arthur, the suggestions for fertilizer for den king that I have seen have been in low nitrogen. e.g. wilford neptune's growing notes are 9-30-25, but I have not been able to find anything like that where I am -- hence my question about the ms_minnamouse formulation.
It is difficult for me to replicate the precise natural conditions of Queensland or northern NSW for my kings, so I am trying to do what I can to improve things for them. If that means a bit of "unnatural" fertilizer, I will certainly give it a go, along with the other advice and notes contributed so kindly by you and other posters in the orchid forum.