Which fertilizer?

[tucker85]

I’m having problems with bud drop. Out of 16 new buds on one catt, 6 have turned yellow and dropped off. I've been growing orchids for 7 years and this is the first time I've had this problem. There have been no temp fluctuations here in south Florida. I’ve been treating my orchids every month with Orthene for insects and a combination of fungicides. I feel confident that this is not an insect or fungus problem. Therefore I assume it’s a nutrient problem. I switched to MSU this year and it has a much lower amount of phosphorus in it (13-3-15). But I also started using liquid seaweed which stimulates root growth. Since flowers and roots require a lot of phosphorus I wonder if the tremendous root growth has used up the limited phosphorus in MSU leaving very little phosphorus left for blooming. So my question is, what fertilizers are you using? Do you supplement with a high phosphorus blooming fertilizer? If so, how often do you use the bloom fertilizer?

[WhiteRabbit]

sorry - I can't help with your question - bumping so that hopefully someone who can will see this

[quiltingwacko]

I am bumping this again so that someone with more catts and more expertise, can answer. Few of my catts are big enough yet to bloom. Carol

[orchidsamore]

I am a commercial grower and try to eliminate Phosphorus from my plants as much as possible.

There is enough Phosphorus in Florida water that additional Phosphorus is not necessary.

There is no scientific proof that phosphorus aids flowers. A total deficiency will cause problems but that is almost impossible in Florida. There is scientific proof that Phosphorus kills beneficial microbes in your potting medium.

Phosphorus fertilizers are illegal to use in Florida during the rainy season if the water runoff can get into the ground water. Phosphorus is the cause of the destruction of the Everglades .

Plants absorb Phosphorus extremely fast. Studies at the University of Florida show that an orchid absorbs 50% of the Phosphorus applied in the first 20 minutes. It then takes 5 years for some forms to dissipate.

You should consider yourself lucky that you have not had bud blast like this in seven years. Commercial growers always have some it is part of nature.

This summer the heat variations and late rains have made everything difficult. My shade houses range from 70-105 everyday. It went from 40-104 everyday in the winter. Flowers can die in a matter of days after opening in this heat. The cold winter delayed blooming on everything. It has been a tough year on flowers.

I would stay with the low Phosphorus fertilizer you are using and stop worrying.

If you want to know more I will be reping the OurVitalEarth brand of organics at the Mounts Botanical Show September 11-12 in West Palm Beach. I will have many root displays of plants showing the benefits of different growing conditions.

The show is free admission and many of the best growers in Florida will be there. Dr. Martin Motes was a guess speaker last year (as was I) and he probably will be a speaker again.

[Lagoon]

Hi Tucker
I'm not sure which kinda water you're using whether it be RO, distilled or just plain tap, but many of my catts did not like the change with distilled and MSU. Mottled leave coloring with fewer flowers for almost a year.

The went back to the their normal growth and blooming pattern once I went back to regular med-hard tap water avec the msu ferts.

I'm not sure of the cause in you're case with the yellowing buds. But I feel that catts really dislike the lower calcium levels.

I would knock off with the seaweed feeds as bloom time approches, it maybe confused about what it should do - do I bloom or grow roots?

You seem to be using Orthene fungicides & on a very regular basis, are you spraying out of prevention?
Could this be adding to the cause of the stress factor you are now seeing? Just something to think about

Photos would be great are you able to provide any pictures?

[Brotherly Monkey]

"treating my orchids every month with Orthene for insects and a combination of fungicides"

hiow long has this been part of your growing regimen? The reason i ask is that when i use orthene for an infestation, my flowers seem to wilt faster than expected

[Ray]

Jerry is right about the phosphorus demand of orchids - it is very small, and they store it away for later use.

There are three classes of uptake action and nutrient retention by the plants -

1. totally controlled by availability (concentration) and cell wall permeation,
2. that, like the phosphorus, that is controlled by concentration, then stored, and
3. ions that are actively "pumped" in by the plant.

Gloria - I cannot imagine what problems the use of RO plus the correct MSU formula would give you. I switched as an experiment, and my plants leaped for the sky. Can you tell us more about your feeding regimen?

[tucker85]

Thanks for all the great advice. You all had some interesting and educational comments. Jerry, I will definitely get to the Mounts Botanical Gardens in Sept.. Thanks for the heads up on that event. I don’t usually expect to see orchid events during the summer in Florida. Thanks again to all of you for your help.

[tucker85]

Originally Posted by Brotherly Monkey

"treating my orchids every month with Orthene for insects and a combination of fungicides"

hiow long has this been part of your growing regimen? The reason i ask is that when i use orthene for an infestation, my flowers seem to wilt faster than expected

I use an insecticide and two fungicides monthly from April through Sept.. During the winter I periodically use an oil like Organocide alternating with Safer soap. This regime has worked pretty well for me since I had a bad scale problem several years ago. But it may add some stress to the plants. I use the mildest dose.

[tucker85]

Originally Posted by Lagoon

Hi Tucker
I'm not sure which kinda water you're using whether it be RO, distilled or just plain tap, but many of my catts did not like the change with distilled and MSU. Mottled leave coloring with fewer flowers for almost a year.

The went back to the their normal growth and blooming pattern once I went back to regular med-hard tap water avec the msu ferts.

I'm not sure of the cause in you're case with the yellowing buds. But I feel that catts really dislike the lower calcium levels.

I would knock off with the seaweed feeds as bloom time approches, it maybe confused about what it should do - do I bloom or grow roots?

You seem to be using Orthene fungicides & on a very regular basis, are you spraying out of prevention?
Could this be adding to the cause of the stress factor you are now seeing? Just something to think about

Photos would be great are you able to provide any pictures?

Gloria, thanks for your reply. I do plan to stop the seaweed at the end of Sept.. I use regular tap water with my fertilizer routine and I have to admit that I have never had the water analyzed so I don't know what's in it. The insecticides and fungicides are low dose for prevention. I use them during the spring and summer. I had a bad scale problem a few years ago.