Spray fertilisers

[Freddie]

Hi all,

a friend bought me an orchid spray fertiliser last year for my birthday (I had asked for a Paphiopedilum, but only got the fertiliser , as my friend did not want to feed my "unhealthy, obsessive habit". No idea what they are talking about ). I have never used it yet. On the bottle, it says to spray the leaves. Now I am not quite sure how that would work. Can plant absorb nutrients through their leaves?!

Have you ever used them? What are your thoughts?

[tucker85]

Yes, orchids and other plants can absorb nutrients through their leaves. I don't know if the uptake of nutrients is as efficient as it would be through the roots. I have used foliar spraying for some of my nutrients in the past.

[Freddie]

Tucker85, thanks for that. Might try using it on some of my orchids currently on bloom/spike. Still don't see how it can be as efficient as a root fertiliser. Then again, I'm no scientist I have some miniature orchids (such as Leptotes bicolor). Would you use the spray on them too? They have tiny little leaves. I suppose it can't hurt to try

[Ray]

I have always argued that foliar feeding is not a very efficient technique with orchids, assuming that the lack of leaf stomata, especially on the upper surface of the leaves, renders it futile.

Based upon discussions I've had with others here, I did some digging and found that I was wrong on a number of counts.

1) Liquids will not pass through stomata in the first place; they're for gases only.
2) Liquids can however, pass through cavities or channels known as ectodesmata that reside on the leaf surface near stomata.
3) Interestingly, polar species within the solutions (most of the ions in fertilizers, for example) are very poor about passing into the leaves, but non-polar species (like urea) are passed preferentially.

Despite correcting past incorrect assumptions, I still feel that most "foliar" applications drip into the medium, and are absorbed through roots.

[Merlyn]

I spray fertilizer every time I fertilize my plants. Make sure to spray under the leaves where the stomata are. I'm not sure, like Tucker says, how efficient it is but it doesn't hurt them and I've been doing it all along for years. I KNOW it's very good for the air roots after they've been watered first ! It's also good for my Dinema polybulbon that seems to like its roots hanging outside the pot much more than inside the media ! So, I guess it's more of an air root feeding routine !

[Freddie]

Merylin, this one is amazing!

[Shiffdaddy]

Awesome plant Chryss

[NatalieS]

Originally Posted by Freddie

Tucker85, thanks for that. Might try using it on some of my orchids currently on bloom/spike. Still don't see how it can be as efficient as a root fertiliser. Then again, I'm no scientist I have some miniature orchids (such as Leptotes bicolor). Would you use the spray on them too? They have tiny little leaves. I suppose it can't hurt to try

Freddie, I'm based in Ireland as well - where did you get your minis from?

[Freddie]

Natalie, actually got them in the uk. Aren't orchids hard to find here?

[NatalieS]

Originally Posted by Freddie

Natalie, actually got them in the uk. Aren't orchids hard to find here?

Did you order online? I find it nearly impossible to find decent orchids here, and they very rarely have labels. The only properly labelled plant that I've managed to find was from Woodies of all places - a Den. Queen Emma.

Sorry for high-jacking the thread by the way. Is the spray fertiliser you have by any chance Orchid Myst? I use it sometimes on the underside of my den leaves. I have read that dens do respond to being fertilised that way. I don't have another den, so I can't experiment with it and can't say for sure if it works.

Natalie