When to fertilize with blooming fert?

[Ray]

I like that philosophy!

[Beallara49]

I have been using Repotme's 13-3-15 MSU formulation diluted half strength twice a month. I use filtered tap water. Do I need to find something with higher P? What do you use for Ca-Mg supplement? I have heard that not all Paphs need extra calcium. Do you supplement all your plants or just the ones that are supposed to need more?

[SouthPark]

Originally Posted by Beallara49

What do you use for Ca-Mg supplement? I have heard that not all Paphs need extra calcium. Do you supplement all your plants or just the ones that are supposed to need more?

I've just been using a bottle with this label 'B.A.M liquid calcium complex' written on it.

I think your plan of 2 times a month is just fine.

I'm just on a once a month plan. I've just been giving it to every orchid I have ----- including paphs, catts, vanda, Fdk, catasetum types, dendrobium, oncid, psychopsis etc. Absolutely no issues. All the plants are extremely healthy. Relatively weak application. Good lighting, good airing, and good draining media, and letting my pots dry out every now and again - with a day of no watering (such as dry out once every four or five days) has been my procedure ----- with a few exceptions only.

Eg. For small plants growing in relatively small pots in volcanic rock media and getting lots of sun and airing, it might not be a good idea to have a day of dry-out ----- only because the media just gets dry already when the pots are fairly small. So ----- just have to play things by 'ear' (or by eye, or feel) sometimes. It depends on the media used, and what the conditions are. Just like looking after ourselves, each grower eventually knows more or less what to do - depending on conditions.

[Orchid Whisperer]

Originally Posted by Beallara49

I have been using Repotme's 13-3-15 MSU formulation diluted half strength twice a month. I use filtered tap water. Do I need to find something with higher P? What do you use for Ca-Mg supplement? I have heard that not all Paphs need extra calcium. Do you supplement all your plants or just the ones that are supposed to need more?

You don't need more P.

A good inexpensive Ca-Mg supplement: a teaspoon each plaster of Paris and Epsom salts per gallon of water, let that stand/dissolve, then add a cup or so of the solution per gallon of water that you will use in your plants, maybe once a month.

[nuriko1set]

Originally Posted by Ray

This has turned into a really good discussion!

Most tap water supplies have plenty, and it is possible to overdo it, so I think it's a good idea to have some idea of the chemistry of your water before adding more.

As to the nitrogen loading, I wasted many years thinking that "high nitrogen" was a matter of the fertilizer ratio, but as Roberta wisely stated, its the amount applied that counts. It is possible for example, to overdo nitrogen with a 3-15-10 formula (any formula containing N), yet by keeping my application concentration low, I do not do so with K-Lite, a 12-1-1 formulation.

Fertilizer is important, but not all THAT important. An orchid is about 95% water. Of that remaining 5%, about 95% is carbon, oxygen, and hydrogen, obtained from the air and water. Of that remaining 5%, about 80% is nitrogen from fertilizer and that remaining 1% constitutes all of the other nutrients, combined.

That was a very good thread of information! Thank you all the previous growers for your contribution of the thread!

So from reading this post, I can deduce that we can use tap water? I've heard/read a lot about using rain water, reverse osmosis, or distilled water. I've been using a combination of distilled, tap and rain water. Does that work? Or should I not even bother with distilled (expensive) and rainwater (a lot of time)?

On the subject of the bloom booster, I actually received one from a relative for the holidays and since I now have it, I am very tempted to use it. It has a 11-35-15 concentration, which is lower in Nitrogen, if I were to use it, I will dilute it to 1/4 strength. But the question is, will it do harm to my spiking orchids? I have 3 orchids in various stages of spiking and budding and I am ECSTATIC!

Phal. schilleriana - just beginning to grow a spike - it's around maybe close to 1/4 inches long at this point.

Cattleya Pot. Dick Smith Paradise - it arrived with 3 large sheaths in October, and just a couple of weeks ago, I noticed that 2 sheaths have started to develop buds. There are 2 buds in each sheath and each of the buds are around 1/4 inch. long right now.

Phal. Leopard Prince - it has 6 developed buds and the closest bud is more than 1/2 big and looks close to popping open. ( this one I feel is too far gone to add bloom booster or any fertilizer, does that sound correct?)

Please let me know your opinion on if bloom booster should be used for any of the above plants. I am trying to form into a routine of using some probiotics, max kelp and fertilizer in a weekly or bi-monthly basis, and have watering rests in between. Am I correct to assume that I should not continue the regular routine during the spiking/budding stage?

I have read that if I were to use bloom boosters, it's better to use it sometimes before the spike grows? Is that right? Or right after growth period? I'm a little fuzzy on that. It's difficult to figure out when that is since all my plants are very new and most likely off sync with their natural seasonal growth time frame. It is weird that the Dick Smith is now starting to form buds in the middle of the winter? Anyone has any opinions on this?

On another note, Ray, you are VERY good at math!!

Thank you all so much! have a great start to 2021.

[Roberta]

A so-called "bloom booster" does not boost blooming. Excess nitrogen can encourage growth at the expense of flowers, and so at some point a formulation that is lower in nitrogen relative to the other major ingredients was invented to supposedly let one fertilize without overdoing the nitrogen. However, orchids really don't need much at all of the other two (phosphorus and potassium) Ray is better at explaining it (and its history) than I am, but the short answer is that "bloom booster" formulations mostly just enrich the manufacturers by selling more "stuff". With regard to nitrogen, if you want less of it when the plant is growing slowly, just use less of your basic fertilizer. For the Cattleya and the Phals, no change in regimen is needed at all. (There are some others, such as many Dendrobiums, that need to have no fertilizer at all in the winter when they "rest" or slow down significantly, but for your three, that is not the case) So just continue the "once weekly, weakly" procedure. Don't cut back while in bloom... but don't change or or increase it either.

[Mr.Fakename]

Originally Posted by nuriko1set

So from reading this post, I can deduce that we can use tap water? I've heard/read a lot about using rain water, reverse osmosis, or distilled water. I've been using a combination of distilled, tap and rain water. Does that work? Or should I not even bother with distilled (expensive) and rainwater (a lot of time)?

I water everything from the tap, even live Sphagnum.
There's some buildup here and there, but nothing serious and no harm as I keep pots moist/flush regularly.

Getting the water report from your town will give precious insight on how good or bad it is.

Congrats on the blooms and happy New Year to you too!

[estación seca]

If your tap water has calcium and magnesium you can mix that with distilled, rain or RO water. In such cases you don't need CalMag fertilizers. Read your water utilitie's annual water quality report.

[Roberta]

I totally agree with ES, find out what is in your tap water. What comes out of the faucet in different places ranges from New York City or San Francisco where the water is so pure that it is fine for Masdevallias (and may need a cal/mag supplement), to much of southern California and other dry areas where it is "liquid rocks". Phals are very forgiving, in most places tap water is just fine for the purpose.

[nuriko1set]

Thank you Estacion and Roberta! I will check the water quality! Does the report usually come in through the mail with your utility bill? Or is it something I have to dig out by calling the utility company?