There is a distinction between repotting and potting up, and I'm not sure where 'transplanting' falls in between the two. There's nothing to stop you from potting up whenever you wish, but tropical and subtropical plants (houseplants) are (from a physiologic perspective) best repotted in the month before their most robust growth, which for you would probably be Jun or early Jul. Some plants might be better to repot immediately after blooming, if your primary concern is a pretty plant and not what is best for the plant's vitality. The best answer for the fertilizer question is not "Stop fertilizing on X date" or even "withhold fertilizer when the plant is not growing". When you should or shouldn't fertilize depends on the relationship between plant size, growth rate, and most importantly, your watering habits and how well the soil drains. In the winter, I fertilize every time I water with a weak solution of fertilizer, but I use fast (draining) soils and flush the soil with the solution every time I water. You cannot do that if your soil is slow or you water in sips, but if you look at the whole picture, slow soils and/or watering in sips are bad either alone or in combination. Plants are growing even if you cannot see them growing. They need nutrition available in the soil to grow and keep their systems orderly. Advice to halt fertilizer ignores the needs of the plant in the assumption that you ARE using a slow soil and watering in sips, because if you are not, if you are using an appropriate soil and watering correctly, the advice is wholly inappropriate. An extrapolation of what I just said might be that if you DO need to stop fertilizing for fear that salt levels will rise too high, you are using an inappropriate soil or are not watering correctly. That isn't to say your plants will assuredly die if you don't use an appropriated soil and water/fertilize appropriately, but you will assuredly be making a notable portion of your plant's potential vitality unrealized. Al

First of all, according to various people, you may want to reconsider keeping your catfish and pond fish together. I posted a link below - or you can do a search yourself on the subject. In our pond in Upstate NY (similar in zone to you), I remove all my tropical plants in early October. We cut back our hardy water lilies which are planted directly in the pond and drop to the bottom the other hardy plants. Our pond is 3 feet deep and approx. 3,000 gallons so the fish overwinter in the pond. I don't know what you should do with a pond that small. We purchased a plastic 100 gallon tub at Country Max for our tropical plants, and I think that would work well for your fish if you decide to bring them indoors. You would have to add a pump or air stone for aeration and something for filtration. My husband altered the "plug" with a faucet and we can drain it pretty easily with a garden hose into our basement sewer come spring. Here is a link that might be useful: catfish in a pond

I usually feed my plants with a lightly tossed handful of slow release pellets when they start active growth in April and usually again in mid-summer. I throw compost around when I have it. I stop when I see the gardens winding down, as I feel they are doing, and the days are definitely shortening, and getting cooler. If something is in active growth, you could still feed it, for example, mums, an annual you are trying to get the last hurrah out of, and I have snaps that have just been sitting around and now are starting to really bloom (I guess in response to the cool weather) and so I could feed them. That's my method, anyway.

I am reading through the old stuff to get more knowledge. I found this question and I had the same questions when I first started too. So maybe I can help. Here's what I do. When tray 1 is full of VC - then you add tray 2 and likewise for tray 3 etc. When tray one was virtually full of VC I stopped feeding for a week (I am a once a week feeder so they went 2 weeks without food. I added tray 2 - with bedding only (week 1 of waiting). Then I fed only into tray 2 as there is food left in tray 1 - and they will live there for some time. So they don't all move up right away - but most will in about a month or two. Some will move down into the moisture collection tray - so look there when you add trays - you can dump them into the new tray with the VC they have made in that tray (there shouldn't be too much) and this starts the action going in the new tray. When I added tray 3 - I moved tray 1 to the top so I could use the VC easier - and keep the lid off occasionally - so the worms move down. So I have an "old tray" on the bottom - mostly VC some food (still being processed) and virtually no bedding. The middle tray is the feeding/working tray where I add new food and bedding once a week-ish. The top tray is my VC tray - and I pull VC from there for my garden. This saves me from dumping - and doing too much sorting. I put the VC in a pie-tin and pick trough that (and store it in the VC bin so it is picked through and ready to use) - I find I have a few cocoons - rarely any worms and a few shreds of envelope windows that didn't get composted (I toss those out and return the cocoons to the bin). This works for me (so far) as I have a small system and it is for home use only. Your results may vary.