Denver has asked Colorado’s public health department for a waiver of some of the state’s coronavirus “safer at home” restrictions to allow Denver Botanic Gardens to reopen its two sites and allow visitors to return in limited numbers.

The city also plans to request a similar variance to allow the Denver Zoo to reopen with some restrictions, and will make that request of the state as soon as possible, spokeswoman Theresa Marchetta said Monday.

Denver officials feel that since the botanic gardens are largely outside, they ought to be treated similarly to parks, trails, golf courses and open spaces, which are open to visitors, according to a May 12 letter signed by Mayor Michael Hancock and Robert McDonald, executive director of the Denver Department of Public Health and Environment.

The variance request details a reopening plan for Denver Botanic Gardens, and said the attraction would require visitors to wear masks and schedule visits solely by reservation, with online ticketing for two-hour windows. The organization also plans to limit the number of visitors on its properties to between 200 and 250, and will put social-distancing practices in place. Staff members will be screened for COVID-19 symptoms and sent home if they appear sick, according to the plan.

Denver is one of at least 33 Colorado counties that have asked the state to loosen some local “safer at home” restrictions. Variances have been granted in at least nine counties, according to the Colorado Department of Public Health and Environment. In some places with few novel coronavirus cases, movie theaters, restaurants, gyms and churches are being allowed to reopen with some precautions.

The request for Denver Botanic Gardens — which has not yet been approved by state officials — asked that the site be allowed to reopen as early as Monday, but its two sites, on York Street in Denver and at Chatfield Farms in Littleton, remained closed Monday.