Any tax if I sell land that forms part of garden?

Question Is there tax to pay on the sale of land which forms part of the garden of the only residence if owners continue to live in the remaining part? If part of the income on the sale is then given to children as a gift is that also free from tax providing the parents survive the 7 year rule?

Arthur says:

The capital gains tax exemption for a main residence includes grounds not exceeding half a hectare (approximately 1.25 acres), or such larger area as is appropriate to the size and character of the house. If you sell some of the land, perhaps for building plots, the sale is covered by the exemption so long as the land was enjoyed as part of the garden and grounds, and is sold either before the sale of the house or at the same time as the sale of the house.

Gifting part or all of the proceeds of the sale to children is like any other gift (PET) as far as IHT is concerned, if the donor survives seven years it falls out of the calculation of their IHT.