Stanley warns: "The danger zone will be those that are stuck in the middle. Around the world we have already seen many of these business flounder as they do not fit into either market segment.
"Garden centres have to focus on either providing the best price or the best value to the consumer. Large outlets will focus on the best price leaving the specialist the value option.
According to Stanley the garden centre in 2020 will look completely different in the way it is designed, the way it is merchandised and the way the team sell.
Many of these changes will be driven by the Millennium Generation who think and behave differently to previous generations and by 2020.
Stanley says retailers' focus will be on developing loyal customers, "not because loyal customers will buy more plants, they probably will not as space will be limited, but because they value the experience that you offer and are advocates for your business".
He says online retailer Zappo is already showing the opportunities and how to deliver "happiness" to consumers.
Stanley added: "Successful garden centres will have entered the era of digital marketing and will be communicating with their customer base via handheld smart devices. The consumer will expect the communications to be a smooth experience, but the critical thing to remember is that research shows that 70 per cent of 'memorable' experiences involve being engaging with people.
"This is one reason why customer service will be a thing of the past and the team engaging with the consumer in the garden centre will be so important. The majority of the selling process will have taken place online."
He says "technology will shine" and garden centres will be recommending new plants online using the same format as Amazon. Smart phones will have voice activation based on developments using applications such as 'Lexee' or 'Nina' applications and this will allow for a personal conversation that has been pre-programmed between the plant manager and the consumer.
He says that by 2020 we will also have 'feel' screens on our smart phones and research is being carried out where smell can also be transmitted, ideal for selling plants.
Stanley said: "The garden centre consumer will walk into the garden centre having already engaged with the business on their smart phone, they will be checking on the product on offer in the centre on their smart phone and looking at consumer reviews of the product, rather than just relying on the garden centre teams advice.
"They will be looking at videos of plants growing and having a video conversation with their garden friends on the plants on offer whilst in the centre. They will be in the garden centre looking for inspiration and engagement with the team. The consumer will be making buying decisions based on what friends are saying and will be selecting an independent garden centre that inspires them."