I bought my lavender plant about a month ago and had done some research before buying it. However, I had been busy and hadn't watered it much and left it indoor instead of leaving it outside in the sun. Also, my sister watered it too much when I knew that lavender plants do not need much water. Is there any way I can get my lavender plant to get back to it's healthy state?

Toss it! Lavender needs a Mediterranean environment...full sun and fast draining soil. It still has to be watered on a regular basis though, and will never be a house plant. You could try cutting it back to a few inches and putting it outside, but I think it's too late.

time to start fresh.

Just buy a new one and read the label for how to care for it. They like hot sunny conditions outdoors but will need thorough watering then left to dry out slightly.

It does look like it's beyond saving. Did it start to wilt like that when you were not watering it or only after your sister started over-watering it? I have had a lavender (Lavandula dentata) as a houseplant for a number of years. It lives on a sunny windowsill in winter and outdoors in its pot in summer (after being gradually acclimatized to the outdoors).

One thing I have found, and it surprised me, is that it wilts very quickly on a sunny day on the windowsill, even in winter, and needs watering far more often than I would have expected. If yours started drooping before your sister started watering it, then that would indicate insufficient water rather than too much. If it had gone beyond what is appropriately called the "permanent wilting point" any amount of water that your sister gave it would not have brought it back.

Hello kiwicheese, that self watering container is not ideal for it and being overwatered too on top of it, and the plant needs more direct sun and drier growing conditions, your media is so peaty needs to be well draining and girttier, so all that happened to it is not in its favor, hence the decline of your plant.

I do tend to agree it is beyond recovery at this point, the roots may be too rotted already. Just get a new one, and learn from this experience so you can start again and still take advantage of the summer growing season.

Don't feel bad, we all learn as we go!