I put earthworms in all of my container plants. They are both red wigglers and night crawlers. Red wigglers will mostly stay at top and night crawlers will stay near the bottom of the pot, but both kinds will tunnel around the potting mix, leaving their vermicasting (wormpoop) behind. I put in big lumps of clay for the nightcrawlers.
Over the years, I have found that the plants that survive neglect — whether Insufficient active fertilization or watering — are the ones that had the earthworms minding them. Ones that were growing better and healthier than expected -or in comparison to another- inevitably had 2 or 3 resident earthworms when finally uppotted or planted out.
For starters, give your plants your kitchen leftovers, keeping in mind they don’t like salt, but they do like a bit of natural sugar. In the winter when I grow tomatoes indoors, I give them all of my used coffee grounds and tea leaves — dump In the watering jug (recycled juice jug) and water. The dregs become mulch on top of potting mix for the red wigglers. Any leftover beverages including coffee and tea, juice, milk, etc. nothing alcoholic — but you can put that in the watering jug and use to water them a few days later. When beverage container is empty, swish with water and save in the watering jug. Use your judgment — they don’t need a lot, too much may be too concentrated.
I save grain and beans rinsing water and dry beans soaking water to give to the plants. Also some beans recipe calls for dumping the first soak/boil water and cooking with fresh water — definitely Save that. Also, any vegetables blanching water (no salt). My DD’s like edamame, and I think the ones pods taste best when buying them frozen. I save the dark green water after cooking them.
I cook pasta without adding salt and save the drained pasta cooking water to cool and give/water the plants. I don’t use this water for particularly salt-sensitive plants since some pasta are made with havy amounts of salt but it can be given to salt-tolerant plants. Tomatoes are borderline, I think. It depends on variety.
Consider keeping a vermicomposter or bokashi fermenter if you have a space for them indoors or outdoors. However, I only keep them indoors during the winter, in the garage. Save all Vegetable scraps and leftovers and feed the worms or the bokashi lacto-fermenting bacteria.
Doing it this way, you only use what you yourself eat. Organic produce, eggshells, etc. oh yeah eggshells. I save hard boiled egg shells to give to the worms — ground into powder in old coffee grinder. I also sometimes put the hard boiled eggshells into watering jug without grinding them up. Whole banana peel, citrus peel... etc. The jug looks kind of like a sangria jug then. This lasts for a few days in the winter while I keep adding water and watering with the leached nutrients. If the additions start to spoil, I drain out the water and put the scraps in the vermicomposter for the worms.
Do you have space for outside compost pile? I mentioned vermicomposting and bokashi because they take up very little space, but if you can do a full compost pile, then you can recycle not only softer kitchen scraps but yard and garden trimmings, too. All your safer papers. Raw shells go directly into the outdoor compost pile because I’m too lazy to sterilize them, but some people bake or boil the shells for use.
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