Lemon Tree

I have a lemon tree which is about 5 years old. It is in a pot which spends the summer on a south facing patio and the winter in a north facing glass fronted double glazed porch. Each year the fruit has set but turns black before ripening. What is the likely cause for this and what can I do about it?

Is it warm enough in your north facing porch? A lemon takes months to ripen. Do you feed it regularly? It likes rainwater, a good soak when dry rather than little and often. Was it grown from a pip? Sometimes pip grown plants never fruit properly. Best to get a well grafted plant. It doesn't like sudden changes of temperatur either.

It was a grafted plant. I use rainwater when the soil is dry. The minimum temperature we have monitored in the porch has been about 6 deg C. It has been fed regularly.

When the blossoms come out, 6 degree not enough, sure.The blossoms like to stand in full sun, wet surface in the morning and evening and worm feeds. Sometime the winter weather is more effective outside than in cold room inside. If you have a day with sun, no cold wind, put it outside to the sunshine for some houres...(not under 6 degree!), greetings.ThaiGer.

I'm afraid I don't think 6° is warm enough either. They come from warm countries. North facing is not really the right place for it.

hello onemore, under 13 degree C! they not blooming. Please look HERE , it's help for  growing inside over the winter...you can grow lemon tree in UK. But you have to know something about citrus fruit trees.Greetings, ThaiGer.

Hello Celia, I have 2 lemons and 1 orange tree. They are in my heated conservatory/ orangery and doing very well. They are covered in fruits and I have been using the fruits all Christmas and wiinter and now! They are sat on the sill facing south. If ever the Sun comes out then they get it as long as the sun is shining. I feed them every week and use (oops) tap water!. I am quite sure during winter the temperature has dropped below 5 degrees if not lower! I think South facing spot is the ideal situation if you have it. Sunshine is very important for the flowering and I think that is the only thing I am doing right