As is probably clear, I unfortunately don't really have the budget, time, or space to make my own fertilizer. Just thought I'd mention it...

Why not use the same product for your herbs as you do your houseplants? Soluble fertilizers pose no health risk whatsoever to you, even though you are going to be eating the plants. And there really aren't any benefits for the plants grown in containers.

If your houseplant fertilizer doesn't contain any trace elements (some do, some don't...it's on the label), you might consider supplementing with a fish or kelp or fish/kelp product occasionally. There are gobs of such products on the market from reputable mail order houses. Google 'organic houseplant fertilizer'.

Just to expand on rhizo's comments a bit.......:-)

This topic comes up periodically here. And those who do a great deal of container gardening typically concur that organic fertilization of container plants, especially those grown entirely indoors, is a tricky proposition at best. Organic fertilizers require the activities of soil organisms to convert the nutrients they contain into plant accessible soluble ions. And few potting soils contain these organisms in any kind of necessary populations (if at all) to be able to successfully make that conversion. So you run the risk of NOT supplying your plants with adequate levels of nutrients to maintain healthy growth if you rely only on organic ferts.

As rhizo suggests, any water soluble houseplant fertilizer will be a better approach and have no adverse effect on your ability to consume the herbs. And these can be found anywhere, even at your local grocery or box store.

I might as well toss my hat into the ring and agree with Dori and Pam. In the end, the elements absorbed by the plant are exactly the same whether they come from soluble fertilizers or broken down organic sources. If you'll allow me to be a little loose with the term 'food', plant foods are salts. Salts are what plants use as the building blocks to do their growing and to maintain their systems. The plant doesn't know or care if that salt came from a soluble fertilizer or from compost. They want a full array of the necessary elements 'in the right ratio' to grow at as close to their genetic potential as possible.

The easiest and most efficient way to provide nutrients in such a manner to containerized plants is through the application of soluble fertilizers, but I understand if you are limited by an ideology. It's difficult to tell you just how to proceed or what to buy, because when you depend on the activity of soil organisms in containers to break the soil amendments you would be using as fertilizer down into elemental form so plants can absorb it, you never know what will be available, what ratio it will be available in, or when it might be available. It's common to apply 3 or more doses of organic fertilizer to containerized plants with no significant impact, only to find later the first two doses carried over in the soil; so when the third dose was applied and they all became available at once, you're left scratching your head over what might have caused the leaf scorch, all the while ruling out over-fertilization because the fertilizer was organic.

Al

Wow, that wasn't at all what I was expecting to hear! I'm quite glad I asked rather than just going out and purchasing some arbitrary organic fertilizer and using it. I'd hate to see my new plants wither.

So currently I just use "Miracle Gro Liquid Houseplant Food" because I can pick it up at the hardward store on the way home from my office. It seems to be the epitome of synthetic manufacture, but it sounds like while my herbs will no longer be considered "organic," they will be completely safe to eat. While I prefer to eat organic, I eat plenty of conventional as well, so I think I can live with this (though I do confess being a bit disappointed).

What do you all mean by water soluble? Do you just mean that it comes in a bottle with water, or is there something deeper?

Many thanks for all of your wonderful advice!

Ooh, and since it doesn' have any micronutrients, any suggestions for something I could pick up that might have them? I read somewhere else that "Foliage Pro" was good but hesitated to use it because I didn't know if it would affect the safety of the herbs, but it sounds like it would be fine based on what you've all said (still makes me a bit nervous, though...)

Thanks again for the help.

I have used a mixture of peanut meal, coffee grounds and sparing amounts of wood ashes, mixed with water overnight to form a slurry, poured on the soil surface and topped off with more potting soil. It worked well for me for basil and tomatoes but I was just experimenting for fun. Obviously, that required some extra space in the container. For the longer term, I prefer chemical ferts for the reasons Al mentioned. Organic or not,it does *not* make your food more or less safe.

In order to get a picture of the difference between soluble fertilizers and organic fertilizers, imagine cell membranes as the fabric chain link fences are made of. Soluble fertilizers moving through cell walls might be considered something like you pushing ping pong balls through the holes in the fence, while organic molecules are more like trying to push basketballs through. The basketballs would have to be broken down into smaller pieces before they would fit. If there is no one standing by to break the basketballs down (if there are reduced populations of soil biota to break down the large organic molecules) no basketball parts get through.

MG houseplant fertilizer is probably not a good choice. I believe the % of NPK is 8-7-6, or very close to that. Plants actually use about 6x more N than P and about 1.5x more N than K. If you choose a soluble fertilizer, you would be better served with something in a 3:1:2 ratio. 24-8-16, 12-4-8, and 9-3-6 are all very popular 3:1:2 ratio soluble fertilizers. Dyna-Gro makes 9-3-6 Foliage-Pro soluble. It's not easy to find, but it's the best I've seen because it also includes Ca and Mg (usually lacking in commonly found soluble blends like MG, Peters, Schultz .....), and it contains all the essential elements in the ratio plants need for normal growth and in a very favorable ratio to each other, also an important consideration.

Al

Many thanks, Al, for the great advice. I think I'm going to just order Foliage-Pro directly from Dyna-Gro. I like that it has all of the micronutrients.

I'm not much of an organic ideolog, but it does weird me out a bit to put fertilizer that isn't specifically labeled as food-safe on my produce. Can you just confirm that to the best of your knowledge, you're pretty sure it's safe to put on food crops?

Also, since I'm going to be paying shipping, any other products you'd suggest from Dyna-Gro?

My say-so doesn't mean much as far as it being safe, but a huge % of the victuals you consume were grown with fertilizers similar to FP, MG, and other solubles. I have a mind scientific enough that I generally cringe when someone uses "Well it works for me" as a clarion call to follow the lemmings, but I've been using it on all the produce I grow in containers for years, and the only time I glow is ...... well, never mind.

You'll need to decide what is right for you, but I never had an issue with eating the produce I grew using MG and other solubles.

Yes, there is another product by FP I would suggest. Their ProTeKt 0-0-3 can be very helpful when you need to reduce the amount of N supplied by reducing your dosage by up to 1/3 (using the 9-3-6 fertilizer) and still be unconcerned about adequate amounts of P and K. It also contains silica, which makes your plants tougher (resistent to insects and disease) at the cellular level, and more resistent to temperature extremes (mostly heat). These are each helpful contributions to plants tended in container culture.

Al

I just wanted to follow up by thanking everyone, especially Al, for all of your help. I ended up getting Dyna-Gro Foliage Pro and Pro-Tekt, exactly as you recommended. I even got a little extra for my girlfriend.

For my own peace of mind, I even ended up calling up the CEO of Dyna-Gro about the food safety issue. He said that all of his products are perfectly safe to use with food crops, though personally, I think I'd avoid the Neem oil on food. I'm not sure if it washes off easily and it sounds like it's biological effects are quite complex (what with confusing the bugs, etc.).

Thanks again!

FWIW - neem oil is used in several medicines, some for stomach ailments, and cosmetics. It's also commonly added to grains (particularly rice) to stave off insect infestations .... your call, though.

Good luck.

Al

You can also use Neem toothpaste, lol!

.... and I forgot to mention Preparation-Neem, though they are probably not interchangeable. ;o)

Al