Which type of fertilizer when in bloom vs. when not?

[RosieC]

I use two fertilisers which come from the same manufacturer and are aimed at orcids. I then follow the advice from the manufacturer which is that the low nitrogen (high potasium) one should be used from "the first sign of bud formation until the last flower drops" and that the high nitrogen one should be used the rest of the time.

I interpret that (either right or wrong) that while they are spiking I carry on with the high nitrogen one, but once buds start forming on those spikes I switch to the low nitrogen one.

My orchids have done both growing and flowering in a vigerous manner under this regime. The last two phals I bought have grown 3-4 big new leaves since april and have not lost any of their old ones. (They are also both spiking now).

I've only got a small collection though and as it starts to grow I start to agree with Camille, when some are in bloom and others are not it's easier just to fertilise with one thing on all of them. I'm still using two just now but if I get many more 'chids I may give up on that.

[markr]

For what it's worth, I use MSU type fertilizer (13-3-15) and sometimes Dynagrow (7-9-5) mixed for 150pp N throughout the year on all my orchids (mostly Angraecoids, Phals, Masdevallias, Restrepias, Neos, and some slippers) and they all bloom regularly.

[markr]

Originally Posted by William

How about Vandas? I've been a joke with my friends because I can get pretty much of my orchids to bloom except for my Vandas. They are beautiful but in at least two years no blooms.

I don't grow any actual Vandas, but I'd guess that the first thing to address is whether or not yours are getting enough light - it's probably the biggest reason that orchids fail to bloom, and most Vandas require lots of it. If they're not getting enough light, manipulating fertilizers isn't going to help them bloom.

[Ross]

These answers are all based on the starve and binge principle, sometimes described as weekly weakly or switch from high nitrogen to low nitrogen, etc. I have tried them all. I have been growing since 1967 (that I can document) and before that, followed my Dad's regime. I have finally settled on the recommendations of MSU described here: Plant Nutrition (you will have to read through all the steps). I regularly fertilize with a mixture often referred to as "MSU mix" mixted in RO water to a concentration of 125ppm Nitrogen. There are a lot of trace elements as well as a little bit of Phosporus and Potassium. I never change the formulation over the year. If you follow my postings, you will see a common theme: I get phenomenal growth and great blossoms - sometimes beyond belief, as in a Beallara that has been in constant growth and bloom since mid last summer (over a year!) I use this same regimen with exotic miniatures in my orchidarium (the tank) as well as with cacti, vegetables, herbs, etc. Is it a miracle solution? Nope! Does it provide a constant (yet weak) supply of all the stuff they need for spectacular growth? Yes! My experience is based on my plant list (you can check it on line) of different species as well as my watering regime which is self-taught.

[markr]

Originally Posted by Ross

These answers are all based on the starve and binge principle,

Posts 6, 9, and 12 offer essentially the same advice as yours.

[frostedeyes]

i dunno i think we have loads of technique in reblooming orchids u dont need to follow us. but i think the most important thing is you need enough sunlight to rebloom your orchid, try not to disturb them. Patience is the key. I have killed several orchids already. Then it was this aunt of mine i found out that she's into orchids so i bought a couple of orchids with flower and of course through my dissappointment they all withered and never rebloom. So my aunt again came up and told me to use a pinch of high nitrogen in a gallon of water. Still no signs of blooming. So i tried the peter's 20-20-20 and i also try switching root hormone 15 drops a gallon of water. well the result i have already rebloom 3 orchids and for the first time my oncidium had 5 flower spikes. Trial and error every mistakes make it a lesson. but i think rooting hormone is important the more roots the more nutrients it will absorb. morning sun is also important- depends on the species. (dendro, oncidium, and cattleya is ok)

[Ray]

Originally Posted by William

How about Vandas? I've been a joke with my friends because I can get pretty much of my orchids to bloom except for my Vandas. They are beautiful but in at least two years no blooms.

In my experience, the best way to get vandaceous plants to bloom well is lots of light coupled with lots of food and water. They are "hungry" suckers.

[BobInBonita]

When I first started (in Minnesota with just a few phals) I used very dilute Miracle Grow at every watering. I had good success with many reblooms over years.

When I moved to Florida, the collection and growing conditions changed. My plants performed poorly with Miracle Grow. I attended a class given by Sundance Orchids locally and started using Dynamite with great success. As a result my collection and interest grew.

I started reading and decided to take fertilization into my own control. I used a balanced fertilizer weakly weekly (except when I forgot or rainy season meant that I didn't water at all. Many plants have done just fine with this regimen, but some (especially the phals) seem less happy.

Recently I've thought about going back to the dynamite just for the simplicity and to cover things during rainy season when they need more fertilizer and I'm prone to give less. Unfortunately, the Dynamite granules just don't work for Vandas in baskets - which are doing very well with my balanced weakly weekly (almost) regimen.

Bottom line is that there is a balance somewhere between best for the plant and best for the grower. I keep trying to find the perfect "sweet spot", but it's an ever moving target.

[Ray]

I have had quite a few growers around here recommend a controlled-release fertilizer, supplemented with hand-applied water soluble stuff.

[Cewal]

Originally Posted by camille1585

I use the same fertilizer at the same dose year round regardless of whether they are in spike or not. I use an almost balanced fertilizer (5-6-6 since I can't find anything balanced!) at 125ppm N at every watering. It seems to work for me, since I have several orchids in spike at the moment. I don't use bloom booster since I just don't have the time to give 2 different ferts each watering depending on what plant needs what.
This subject has been discussed a few times here on OB, and I know that several people do the same thing with whatever fertilizer they are using.

What does '125ppm N' mean? (Hope I don't sound TOO stupid.)