Household or garden waste
You should not get rid of household waste by burning it as this can cause pollution or harm people's health. Please compost or recycle it instead.
There is no law to stop people from burning garden waste or rubbish in their garden, but if the smoke it causes is a nuisance then you could be served with an abatement notice under the Environmental Protection Act 1990. For an abatement notice to be served Environmental Health Officers would have to witness the burning and decide that it is a nuisance. It would also have to happen regularly.
If you think the fire is burning dangerously then you should contact the Fire Service.
Trade waste
It is an offense to burn waste from a business (trade waste). All trade waste must be disposed of using a licensed waste contractor. The laws on this are enforced by the Scottish Environment Protection Agency (SEPA)