Manor Infant and Nursery School in Buckland held a 'Big Dig' on Saturday at which a 'living fence' was planted around its boundary by pupils, parents and councillors, including the Lord Mayor Frank Jonas.
Head teacher Helen Castle said the event had been 'an overwhelming success' with a bigger than expected turnout and said it would help pupils connect with nature.
'Because of Covid we've not really been able to do the sorts of events we would do before in encouraging outside learning,' she said. 'Giving the children a sense of ownership of everything we've planted is really important to their development.'
Supported by the donation of 500 young trees from the charity Trees for Cities and 20 fruit trees from Charles Dickens Community Orchard, the event on Saturday saw pupils and community leaders plant the trees and install bird boxes across the school grounds over two hours.
The project was launched by the school in collaboration with the Portsmouth Climate Action Board in a bid to transform the 'rather bleak' boundary.
'We had a look at what we could do relatively quickly but would also be a long-term benefit to the school and wider area,' Mrs Castle added. 'Working with the Climate Action Board we came up with this idea and it's been brilliant.
'To have something like this will be invaluable and play a key part in the children's development and the whole process of planting will help them develop their skills and knowledge.'
She said the school was now looking to launch a fundraising campaign to cover the cost of installing raised beds to further the experience.
Nick Sebley, a member of the Portsmouth Climate Action Board, who helped coordinate the project, said he hoped the idea would be picked up by more schools across the city.
'What we are trying to do as a board is set up a city-wide greening campaign,' he said. 'Not only is it good for helping reduce our emissions and lower pollution but it's also a huge positive for people's physical and mental wellbeing.
'It ticks so many boxes and will also boost biodiversity as well as helping children learn about the environment.'