Advice to try to save this indoor lemon tree?

[Startingagainandagain]

I bought this lemon tree about two months ago and it has been kept indoors as advised.

It had a few lemons already when I bought it which I then harvested as they matured but now it is looking a bit sorry for itself and does not seem to manage to grow anything else.

Any idea of what I am doing wrong and how to help it?

Never had one of these so a bit lost...

Repot it in a slightly larger pot with some fresh compost would be my first suggestion. The compost it’s in looks old and dry.

The pot does look small for the size of plant. Repot in ericaceous compost and use rainwater to water it with

And then patience ... I've grown citrus from pips over the years and had precisely one flower and no fruit.

OK great! thank you. I will get a bigger pot and some compost :).

Those leaves don’t seem to be getting any water. Either because it’s too dry, or because it’s been watered too much and the roots have rotted

I put the tree in a new bigger pot with nice compost. The roots did not seem to have rotted. Will see if the change of pot and better feed improves things.

Use rainwater for watering if you can, just put a container outside and catch some. Once it is a bit warmer, the tree can go outside for the summer.

And don't feed it until June at the earliest, or when it puts out some strong new shoots. If it looks sickly, don't feed it at all.

Lemon trees are a pain in the arse, never managed to keep one alive.

No point in feeding till the leaves have perked up

You can get citrus compost, which is usually a bit coarser than ericaceous (so less likely to get waterlogged.) You can also get citrus fertiliser - winter and summer, but I've never used the winter one. Water with rainwater if you can, but I don't always have any available, and sometimes tap water (even from a very hard water area,) is better than no water.

Thank you everyone for all the comments! really helpful.

The leaves look better this morning already, so a positive sign I hope.

I have a couple of small containers in the garden already to collect rain water that I use on my raised beds (vegetables).

I used some of that water as well for the lemon tree yesterday.

I will put it outside as well when the weather hopefully gets warmer.

I have one that lives outside all year (too big to move inside, but it has a sheltered spot over winter and is more exposed over summer. The others will go out in about a month.

Might be worth changing its position OP. I find this with my plants, once I find the right place I won’t move them, I have one windowsill that seems to revive any plant, even a fern, that was dying, never managed to keep a fern, is now thriving. I bought a begonia in Lidl the other day ridiculously cheap, but I liked the pot it was in, the begonia is looking great now.

As well as up potting it with fresh compost, I'd chop the leaves back and prune the branches back until you see green wick, so any dead branches are pruned off. It will probably be a really heavy prune looking at it, but new compost, regular watering, possibly a citrus specific feed.

Thank you! I will prune the branches as well.

There is no need to feed any plant that has recently been repotted, as there will be plenty of nutrients in the new compost, which will last for several weeks, if not months.

Plants don't need 'food' like we do, it is a misnomer - they make their own food by photosynthesis using light and water. What they can't access (because we have stuck them in a pot) is trace minerals and elements they would normally get from the ground.