Lincolnshire Partnership NHS Foundation Trust was criticised by the Care Quality Commission (CQC) in March 2015.
A re-inspection in April this year found it had made "positive progress" in some areas, but improvements were still needed.
The safety of patients at high risk of suicide had been deemed inadequate but has now been improved.
The trust currently has about 27,000 patients across the county and more than 2,000 members of staff.
Dr Paul Lelliott, deputy chief inspector of hospitals for the CQC, said there was now "good care" for the population served by the trust.
"We saw staff treating patients with kindness, dignity and respect," he said.
The use of volunteers and therapy dogs was praised, as was the patient-run cafÃ© and the range of paid job opportunities, including gardening and car valeting.
In March 2015 patients at risk of suicide were found not to be kept safe, but the trust said it now monitors "ligature risks", which are fixed points which someone could use to harm themselves.
"Heat maps" are also used to show patients at high risk of suicide.
Dr John Brewin, trust chief executive, said: "I am pleased that the work of all of our staff has been reflected.
"Our staff have a real focus on providing high-quality care for our patients and this latest report is testament to that commitment."
Improvements are needed in the areas of care plans, staff supervision, bed availability and delays in patients accessing psychological therapies, the CQC said.
The trust was also found to have good relationships with the community and police.
An NHS mental health services provider has been upgraded from "inadequate" to "good" following a recent inspection.