Geldof was last week dropped as a model for the lingerie brand following allegations that she had enjoyed a heroin-fuelled romp with a US artist.
Responding to the news, Garraway told New: "I don't think Ultimo had any choice but to do it. If they'd kept her on after a story like this they would have been severely criticised and accused of sending out the wrong message to their customers."
The GMTV host added: "[Peaches] has got so much going for her and I really hope she doesn't end up going down the same route as her poor late mother, Paula Yates.
"Let's hope this is the wake-up call she needs to stay on the straight and narrow."
Geldof strongly denied any wrongdoing shortly before she was sacked by Ultimo.