Some of my houseplants were looking a bit sorry for themselves, so over the weekend I gave them a bit of TLC. Here's my procedure for houseplants.
1. Compost any that are dead, crispy, or in any other way a basket-case. Feel guilty. Promise yourself you will remember to water/not to overwater them in future. Make a list of the species that died and remember never to buy that type again.
Half the secret of success with houseplants is to quickly get rid of any that are dying and look terrible.
2. Gently tip each surviving houseplant out of its pot to see if it needs repotting. If it does, the roots will be thick and visible, tangled inside the rootball. If you can see mostly soil and only a few fine roots, it's probably OK where it is. Remember which ones need repotting.
3. Put a couple of inches of water in the bath with some plant food. Stand all the houseplants in the bath, and gently mist them with the showerhead, so the soil gets wet from the top and the bottom. After an hour or so they should all be feeling much perkier.
4. Repot any plants that need it. Just find a slightly bigger pot, put a little potting compost in the bottom and carefully place the rootball on top. Fill in the gaps with more compost, and put a layer on top, firming it down with your fingers. It's important to give the plant a really good drink, but I don't usually bother with teasing out the roots. The roots seem to manage to grow outwards in their own time.
5. Snip any brown, dead leaves and rotten flowerheads off the plants. My mum used to cut the brown ends off spiderplants, and then trim them back to nice points. She called it "giving them a haircut". She could be a bit odd sometimes...
6. Occasionally when you trim a plant in this way, it only has three or four healthy leaves left and looks rather tragic. In these cases I tend to make cuttings. Snip off the healthy leaves with their stems, or sections of the plant, then push them into small pots of damp potting compost. You can compost the stem and rootball. With luck they will begin to root. You can't tell - don't pull them up to see if they have or not. If they die, then they didn't root, and if they stay alive, well they must have rooted. In a while they will start putting out new leaves and grow. Voila - several new healthy houseplants from one ailing houseplant!
7. You can also take cuttings of any plants which are healthy and thriving, of course, and this is an excellent idea. The other half of the secret of success with houseplants is to learn which varieties thrive under your own conditions and combination of neglect/overattention. Then specialise in that variety. Everyone will say "Oh, she's terribly good with begonias (or whatever)", and they don't need to know that begonias are the only things that survive in your house. Tip: spider plants are almost indestructible.