Dozens of households in Lincolnshire applied to become foster carers in the year to March 2022, new figures show.
It comes as the number of people applying has steadily fallen over the last five years, including a significant drop last year.
This year, Foster Care Fortnight, which takes place from May 15 to 28, is focused on "Fostering Communities", and is aiming to highlight the need for more foster carers.
The Fostering Network said society must not "lose sight of the fact we urgently need more foster carers to come forward to care for children locally".
But the latest Ofsted figures show 8,280 households in England applied to become foster carers in the year to March 2022 – the lowest figure in the last five years, and a drop of 26% from 2020-21.
Foster care places are split into two categories, local authority placements, which are organised and managed by the local council, and those delivered by independent fostering agencies, such as charities and organisations that can place children with approved families.
For local authority-managed foster care placements, the number of approved households in the year to March fell by 18% from 2020-21, with just 2,075 approved across England – of these, 25 were based in Lincolnshire.
Figures are rounded to the nearest five.
Mervyn Erskine, chair of trustees at The Fostering Network, said: "We can’t lose sight of the fact we urgently need more foster carers to come forward to care for children locally.
"When a child comes into care needing a foster home, it is essential they can live with a foster carer who can meet their individual needs, in the area they belong – ultimately, everything they need to be the absolute best version of themselves."
The figures also show approximately 25 applications were approved in Lincolnshire in the year to March 2022, though some of these were submitted in previous years.
It means around 230 total households were offering foster care placements at the end of March 2022 – down from 340 in 2018.
Yvette Stanley, Ofsted's national director of regulation and social care, said: "Foster carers make such a difference to children’s lives by providing stable and loving homes. So it’s a real concern that there are not nearly enough foster carers available for the growing number of children needing care.
"Getting foster-care matches right is central to ensuring children’s individual needs are met. However, the shortage of foster carers makes good matching far more difficult and, in some cases, can leave children without the care they need."