fertiliser, different types, different growth periods.

[headbanger333]

Hello all, I am totally ignorant of forums and their machinations. I am an enthusiastic hobbyist living in Auckland, New Zealand. I made a basic error when I started collecting orchids 15 months ago and bought many different types (16) and, of course, it wasn't long before I realised they all required different care and conditions. I have nitrogen food and flowering food but do not know for sure when to apply and to which plant. Surely there must be certain signs that each type of orchid displays to tell me who needs what? I am totally involved with them and, like everyone else, I want to provide excellent care to get the best results. I would be grateful for a Dummies course in fertilising. Thanku

[King_of_orchid_growing:)]

Generally speaking, it is not necessary to go to any great lengths to time a certain type of fertilizer for a certain purpose during a certain season for a particular genus or species of orchid. Many of the commonly grown epiphytic orchids will do just fine with a water soluble 20-20-20 fertilizer all year round. Heck, it doesn't even have to be 20-20-20, even if it is 10-8-10, it's fine. How's this sound for a "Dummies course"? haha

If anybody is unfamiliar with what I meant by saying "20-20-20", that is a ratio. It is the ratio of Nitrogen (N):Phosphorous (P):Potassium (K), otherwise known as the N-P-K ratio.

There are exceptions to what I just said, but for the sake of keeping it simple for now, for someone who is just starting out with orchids, this is what I have to say regarding fertilizers and fertilizing regimens.

If you're growing Aussie terrestrial orchids such as Diuris, Caladenia, Pterostylis, or Thelymitras, that's a totally different story.

Out of curiosity, what kinds of orchids do you currently have?

[Ray]

Ask a dozen growers, and you'll easily get 13 opinions of fertilizers, but I agree with Philip that sticking with one formula - a complete one - is fine. All that "bloom booster" stuff is hogwash.

I will add, however, that feeding is not particularly critical - for a plant to gain 1 kg in mass, it must process about 225 kg of water and only needs about 12 g of fertilizer minerals, and many orchids will take years to grow that much. Because of that, and mimicking what they see in nature, I prefer to give my orchids a tiny amount of fertilizer (about 25 ppm N) at every watering.

And...as other experienced growers here will agree, fertilizer will not "fix" a failing in other cultural aspects. Focus on the myriad of those first, and once you've mastered your growing technique, THEN you'll be in a good position to experiment with nutrients.

[Orchid Whisperer]

To the above recommendations on balanced fertilizer, I would add that providing calcium (Ca) and magnesium (Mg) is beneficial, if they are not already sufficiently supplied in your local water (in my local city water, they are not). For years I have done this by adding a teaspoon each of gypsum and Epsom salts to water once a week. These two minerals also provide sulfur (S) which is also beneficial to plants.

Calcium and magnesium will help plants ward off certain diseases and deficiencies (similar to the way that calcium prevents blossom end rot in tomatoes).

[estación seca]

It will be useful for you to get the water quality report from your water utility. It is generally available online. The amount of dissolved solids in the water, and pH, are of concern to a lot of orchids.

Ray, above, didn't mention the large amount of information on his Web site. You can read all about it under Free Information.

[headbanger333]

Thanku all so much for fertiliser info. The types of orchids I have are: phals, catts, dend, paphs, cymbids, masdevallias, sarcos, miltonias, miltassias, oncids, laelias, zygos, bifrennarias, pleurothallis, pterostylis. As you can see, my love knew no bounds!

[estación seca]

Temperature will be a bigger problem for you than fertilizer.

[King_of_orchid_growing:)]

Originally Posted by headbanger333

Thanku all so much for fertiliser info. The types of orchids I have are: phals, catts, dend, paphs, cymbids, masdevallias, sarcos, miltonias, miltassias, oncids, laelias, zygos, bifrennarias, pleurothallis, pterostylis. As you can see, my love knew no bounds!

Wow...

I'd say temperature is the least of your worries. I'm concerned you may not understand each orchid's growth habits and general environmental requirements, (which includes temperature).

Are you aware that Bifrenaria has a "soft dormancy"? They should be watered less often during the winter.

Are you also aware that Pterostylis has a definite dormancy?

Pterostylis is also a terrestrial orchid that grows underground tuberoids. These tuberoids are fleshy potato-like underground storage organs that consists of cells that are similar to those found in the orchid's roots. These storage organs are very sensitive to being overwatered during their dormancy period. They can rot quite quickly if you do not observe their dormancy period properly.

Remember the first post I made in this thread responding to you where I said that if you're growing Aussie terrestrials like Pterostylis, you can't use the advice I initially gave you regarding fertilization? Yeah, well, here's some new piece of advice regarding fertilization with respect to Pterostylis...You need to be concerned about timing of fertilization. You must stop fertilization of Pterostylis during their dormancy season. You will also have to dilute the strength of your fertilizer solution or use a slow release fertilizer like Osmocote or whatever brand you Kiwis have down there that are like Osmocote.

With Pterostylis, you will also need to learn the skill of storing the tuberoids during dormancy. This can be rather challenging if you've never had to do this before.

Depending on the Paphiopedilum you got, that may be somewhat of a steep learning curve as well... You're gonna have to learn a little bit about pH in association with the orchid's natural habitat, especially if it is a species.

Incidentally, is the Paphiopedilum a species or hybrid? What is the full name?

What is the name of the Pleurothallis? Depending on the Pleurothallis you've got, it could be a quite a learning experience in catering to its needs. These generally do not tolerate being watered with tap water very well. Water has to be low in dissolved mineral content in order for these to do well.

Again, what kind of Dendrobium are you talking about? Depending on the Dendrobium, you could be looking at considering dormancy for the plant.

What kind of Masdevallia do you have? Masdevallias could be problematic with regards to temperature requirements as well as needing water that is low in dissolved mineral content.

What kind of Laelias did you get? Not all Laelias grow on trees in the wild. Some grow on rocks.

What kind of Phalaenopsis did you get? Some of the species Phals, (not all), can be tough to grow for a beginner.

Not all Cymbidiums grow the same way, especially if you're talking about the species. Which Cymbidium did you get?

Same with the Cattleyas. Not all of them can be grown the same way. Some of them have special needs.

I think you need to be very specific about what your plants are. As a beginner, I think taking on this varied a group of orchids without much prior knowledge or experience could end up being a rather disappointing first-time venture.