Garden waste recycling
Any tradesman who removes any kind of waste from your property must be a licensed waste carrier. Anyone found transporting other peoples waste without a license can be prosecuted. Only licensed waste carriers are allowed to deposit other peoples waste at approved recycling centres. If they don't have a license they cannot dispose of it legally. If that waste is traced back to you - you may be prosecuted for encouraging fly-tipping!
A gardener who transports only green garden waste can apply for a free waste carriers license (lower Tier waste carriers license). Anyone who transports mixed waste (building rubble etc) will have to pay for an Upper Tier waste carriers license.
However, this does not mean that a gardener can dispose of green garden waste for free. Many local recycling facilities are for domestic use only and do not accept commercial waste even if it is a result of gardening work at a domestic property. Your gardener will need to visit a privately owned recycling centre who will charge (£) based on weight or van size. These sites will have a minimum charge (£), so your gardener will need to store green waste (£) until there is sufficient to justify a visit to a commercial recycling centre - these are often few and far between and will take time to get to (£).
You can check if a trader has a waste carriers license on this government website: https://environment.data.gov.uk/public-register/view/index
Waste disposal fees can be expensive. Try to home compost and recycle when you can.
Not all gardeners will remove green waste. Your council may also provide a green waste recycling service as part of their regular home waste removal service.