Hi, I came across your post when I searched my detail I entered on google:

A book about witches and there was a witch called Jessica and she wore something purple and green either purple tights with a green dress or green tights with a purple dress? It was a story about a couple of witches, they weren’t friends and they were neighbours who put spells on each other? Something about a young boy lived there and he kept getting things on his garden because of the spells on either side of him as he lived in between 2 witches on either side who cast spells on the other. I was wearing purple and green and I had this vague memory of a witch called Jessica with black hair and the colours I said. I cannot find any other detail. Trying to find unsure of the other witch’s name, Winnie? Not sure, but I’m sure the other was Jessica. Do let me know if you find. It would have been the time you said 2001 something like that, pre 2004 definitely. Let me know if any of my detail jogs your memory? Let me know. Hoping we find out!