mcaren, growing plants indoors is bringing the outdoors into your house. Outside the front door is a doormat. The plant cannot wipe its feet so we have to do so for it. There are organic potting mixes which are free from pests and disease agents. Indeed you can make it for yourself by "steaming" the mix to 160 degrees F. Damp mix, rolled sausage style in wet paper towels, microwave oven, meat thermometer. Avoid manure type fertilizer because they are malodorus or malodoriferous (maybe both). I use 'Osmocote' but regardless of what you use, flush the pot at least once a year; this gets rid of accumulated salts derived from mainly synthetic fertilizers. The simplest way to do this is by submerging the plant (in the pot) in a container of clean water for not more than 30 minutes. Take it out and allow to drain thoroughly before placing it. Return to regular watering when the plant needs it.

I mix potting soil with compost when repotting the plants, about once a year. If the plants need more before I get them repotted the next time I use a weak solution of compost tea.

Fish emulsion is probably something like 5-0-0. It's not a complete fertilizer.

Actually fish emulsion is a complete fertilizer, Robin. the NPK numbers on the label are all above 1 (for all brands I have seen) and all of the minor/micro nutrients are also in it although the labels generally do not indicate this because the amount is variable.

Thank you all for your comments. Actually I only used the organic potting soil because I had some left; I'd used it when trying to saving some of the hundreds of volunteer tomatoes that came up this year in hopes that I could give the plants away (only a few takers...). But I was curious if there were aspects of organic gardening that applied to houseplants (I was and still am very ignorant of the different ways that organic gardening is beneficial). I was also interested in finding whether or not I could use some of the products I already have rather than purchasing a separate product. I am relieved to find that I don't need to create any sort of earthworm or other critter microenvironment in order for my inside plants to be healthy!

Don't let the idea of teaming life in the soil scare you away from your house plants stay in the house. If the Miracle Grow works, then there is already at least some microbe life going on to convert the urea Nitrogen into Nitrate Nitrogen for your plants to eat.

Heck worms in the flowerpots might not be so bad either but I understand you probably want to make sure the containers don't dry out completely or let them stay too waterlogged or the worms will be forced to escape.

I checked the bottle again. The fish emulsion I have is 5-0-0. I'll have to look for another brand that has P and K. Thanks for the info!

Really? What brand is that, Robin? You might like Neptune Harvest Brand. You may have to mail order it, but it's 2-4-1 with all the minors. You can see the breakdown of what is typically in it here.

At the risk of sounding like a shill for these people - but then I see recommendations for Neptuen's Harvest here often - Raingrow 4-2-3 is an organic fert we use on our houseplants - made from composted poultry manure but smells like eucalyptus and tea tree oil, works like a charm and is available in the US as well.

Here is a link that might be useful: 423

I have a couple of houseplants that are watered only with the water that the cockatiels foul up. Seems to work fine, they don't seem to need any additional fertilizer. I don't know how "organic" that is.

I have heard from more than one source that synthetic fertilizers can produce weak growth. This is likely due at least in part to such fertilizers' concentrations, which are usually relatively higher than organics. The user's misapplication can also exacerbate this potential peril. In addition, like synthetic vitamins, synthetic fertilizers do not accurately reproduce all the nutrient elements in the same forms and/or ratios that are typically found, with all their accompanying micro-elements, in nature. Manufacturers of synthetics tend to create ingredient formulations designed for quick, impressive growth at the expense of the long term, well-rounded health of the plant. Perhaps for this reason, synthetics can be harder for plants to process and can cause them more stress. Also, while it is not entirely impossible for beneficial microorganisms to live in a synthetically-fertilized medium, their populations will suffer even in a best case scenario; of course, this negatively impacts plant health. In contrast, some organic houseplant fertilizers out there actually include microorganisms in their formulations. (For example, I just Googled "organic houseplant fertilizer" and found Organica brand.)

What's more, synthetic fertilizers, unlike organic ones, have the disadvantage of producing soluble salts, which, if sufficiently accumulated in the soil, can cause toxicity reactions to the plant (particularly leaf tips). To avoid this, the plant owner must regularly leach these salts out and/or scrape them off the top of the soil and pot.

From an environmental perspective, synthetic fertilizers are petroleum derivatives, and petroleum, as we know, is a non-renewable resource whose extraction and processing can cause considerable environmental--not to mention societal and political--destruction.

Finally, if one has any thought of ever disposing of one's synthetically-fertilized houseplant and/or its soil, then one should realize he/she will be releasing the fertilizer's synthetics and their potentially toxic by-products into the environment--whether it be a compost pile or a landfill.

Yes, you need to add nutrients, and no, you don't need a container soil teaming with life to raise perfectly healthy houseplants. You can probably raise your houseplants with their feet in nothing but Turface, and have results superior to those you would find in most of the compost/peat concoctions you frequently read about.

Using organic fertilizers in your house plants promotes much more rapid soil collapse, so unless you're a dedicated 'repotter', and not particularly 'results oriented, I would suggest you use a synthetic in a 3:1:2 ratio BTW, I draw distinct delineation between a repot, which includes root pruning where appropriate and a complete chance of soil, and potting up, which is simply moving the plant to a larger pot and adding soil. The later practice guarantees eventual decline and ensures the plant will not grow as near its genetic potential and with as much vitality as a plant that has been regularly repotted ..... but I'm straying from the subject here.

Two other byproducts of organic fertilizers in houseplants is their tendency to promote surface algal growth, which turns hydrophobic (water repellent) while the soil still has considerable moisture in it, making it difficult to water properly, and the tendency for them to support fungus gnats & other soil dwellers that enjoy the easily accessible organic snacks you provide.

I use synthetic fertilizers in containers (only containers - believe in 'feeding the soil' for my gardens and beds) and would be very happy to link you to pictures so you can decide for yourself if "synthetic fertilizers produce weak growth". I have absolutely no guilt stress over using synthetic fertilizers responsibly. I wouldn't argue with the self-limiting ideologue over his choices, they are what they are and why argue about choices? - but if results are the goal, I can present an extremely convincing case to the open-minded.

Al