Help! Lemons on my indoor lemon tree gone black (pic attached)

[buzzheath]

I water it a few times weekly but tbh not sure if I’m watering it enough? I do like 1litre usually. Apologies I’m clueless about houseplants and this was probably a mistake to go straight to a tree! No idea why the lemon has gone black. Any advice please? Thanks so much,

Hi, just looking at the pot, is the water able to drain out of there or does it sit inside? Citrus plants like high humidity but rapid draining of water through the soil, they don't like their roots sitting in water.

Not saying this is why the fruit has rotted, most likely a pest has entered it and decay has set in as a result. Citrus are quite challenging to grow indoors as they like the air to be more humid than we usually like it, but you can achieve this by standing the inner pot on a tray of pebbles and pouring water on the pebbles.

They are also hungrier than average houseplants and need feeding frequently, high nitrogen food in the growing season and a more balanced feed in winter (ie with less nitrogen which aids leaf growth). You can buy special feed for citrus plants and also composts which suit their needs for sharp drainage.

@TheNoodlesIncident thanks so much for your response. Theres a layer of pebbles at the bottom of the pot which I thought would help with drainage.

What sort of food should I give it? Also, is watering it a few times a week with a litre of water enough do you think?

Is there any way to rescue it? Should I chop off the blackened lemons?

thank you!

I don't water my citruses so much as you when they're inside (they're currently in the garden for the summer.) They live in the bathroom the rest of the year, which helps with humidity, but is also south facing, do they get a lot of light.

I have some citrus fertiliser, but I'm a bit haphazard on its use, rather than a regular thing, so I might not be the best person for advice.

I'd remove the black fruit.

Agree with EBearhug, pick off the blackened lemons as they're waste at this point.

What I would do with that is remove any outer pot cover which will hold water. It doesn't want to sit in water at all, even a layer of pebbles underneath won't help as it just creates a reservoir. If you can, put it in a terracotta pot with a drainage hole on the bottom and sit it on a tray or big plate with pebbles on. When you water it, perhaps do it in the sink and let all the water run out of the pot before you put it back on its pebble tray. Feed wise, it's probably easiest to pick up a box of citrus feed at a garden centre and follow the instructions on the pack.

The important things to remember is well-draining soil, so water goes through it quickly, and high humidity. (I wouldn't plant any citrus in regular garden compost, it isn't sharp enough. You'd need a recipe one like John Innes No 2, which has a lot of sharp sand/grit in it. So if you repot it I would use something like that.)

If you look for citrus compost, it's worth shopping around. I've seen prices for the same 8l bag vary between £5 and £20...

@TheNoodlesIncident Really helpful, thank you! Will definitely try this in the next few days. A bit annoyed that the online retailer I bought the plant from didn't specify any of this in their "care instructions"!

Yeah,but gardening of any sort is always a battle against things wanting to die, which is why it feels such an achievement when they don't. Besides, apart from the blackened fruit, yours looks pretty healthy, leaves are a good colour and so on.