Earlyworld Nursery, in Bicton Heath, was visited by Ofsted inspector Lesley Bott last month.
She found that the management of the nursery was not effective, the quality of teaching required improvement, and the development and welfare of the children was below that expected.
On a previous visit in 2016, the nursery, which cares for 194 children aged up to five, was rated as good.
In her report, which was published this week, Mrs Bott said: "The arrangements to monitor, supervise and coach staff are not effective enough. Although the management team identifies in staff practice, they do not address these swiftly enough to ensure consistently good quality care and learning."
However, she did note that there was a good understanding of child protection issues and robust risk assessments were in place.
Mrs Bott said that staff at the nursery failed to provide enough opportunities for children, who are non-native English speakers, to use their home language as they play and therefore activities were not well planned.
However, she found that in other aspects, the staff supported the children's learning and monitored the children's progress well.
But she said: "Babies do not have sufficient daily opportunities to experience and explore the outdoors."
With regards to their personal development, Mrs Bott said: "Staff do not always fully consider and effectively meet children's emotional needs when they move up to the next room. Consequently, some children are not well prepared and at times become distressed."
She also found that not all of the children were making the progress they were capable of but she did say that throughout the nursery children were able to initiate their own play and pre-school children were prepared for school.
She said that the staff provided good opportunities for children to develop their literacy skills and staff are vigilant to maintain the children's safety and security.
She added that the children were well behaved who shared and played well together.