Noelridge Greenhouse (Noelridge Park municipal greenhouses)

Producing flowers for Cedar Rapids' public spaces long predates the Noelridge Greenhouse. According to the city, the parks division has grown them since 1930; its first greenhouses, at Bever Park, are described as three 20-by-80-foot glasshouses attached to the maintenance building, while The Gazette dates the first city greenhouse in the park to 1900, 50 feet long and 20 wide. In 1968 the city's garden clubs asked the council to replace that building, which they called small, outdated and deteriorated; money was appropriated the same year, and park officials pointed out that land at Noelridge had been reserved for a greenhouse for years.

The contract for the new greenhouses was advertised on 14 October 1970. Construction of five aluminium-frame greenhouses of 103 by 32 feet began in early winter 1970 and was halted in May 1971 by a building trades strike; a two-bedroom apartment was included to house the city's horticulturist. The city's website and The Gazette place the opening of the five greenhouses on 27 December 1971; the move of the plants began in mid-January 1972, and the ribbon-cutting and first open house took place on 13 and 14 May 1972. The sources therefore speak sometimes of 1971, sometimes of 1972. Plants from the Bever Park greenhouses are still part of the permanent tropical display.

The city marked the 50th anniversary in 2022 with the first of two murals on the front of the building, painted by an artist from Minneapolis; the second, devoted to three native Iowa ecosystems, joined it in 2024.

The complex consists of five parallel greenhouses, numbered 1 to 5 on the plans, stepped along a diagonal and linked to a service building (the headhouse). OpenStreetMap draws them with this staircase outline; the total footprint, headhouse included, comes to about 2,400 m² on that map. The Gazette speaks of five aluminium-frame greenhouses of 103 by 32 feet (about 31 by 10 m), which the 2012-2013 plans bear out: each house is 32 feet wide, with a ridge, 48-inch roof vents and glazed side walls; the sections are in 6061-T6 and 6063-T6 aluminium alloys.

The glazing is mixed. Those plans, drawn by Rough Brothers of Cincinnati for a re-glazing of the roofs (re-bid set of 9 April 2013), call for clear 16 mm double-skinned acrylic panels on all roofs, held by bar caps with a PVC thermal break and EPDM gaskets, while the side walls remain glass. The city's bid of June 2020 states that houses 3, 4 and 5 carry these acrylic panels (about 156 roof panels and as many vent panels broken by the April 2020 hailstorm), whereas houses 1 and 2 are still glass, with 95 panes damaged. Houses 4 and 5 hold permanent horticultural collections that could not be moved during the work.

The city describes a collection of tropical and arid plants, some more than fifty years old; the 2020 bid adds that houses 4 and 5 contain permanent collections. According to The Gazette (2022), the indoor botanical garden includes a banana tree, a cactus garden and an orchid collection. A bougainvillea from the Bever Park greenhouses, moved when the new complex opened, still flowers there, and agaves grow alongside. The Friends of Noelridge mention several banana plants in the "Tropical Rain Forest" section of their conservatory, and KCRG mentions cacti growing up to the ceiling, fish and a temperature kept at 68 °F (20 °C) or above in winter.

Most of the work is production: between 40,000 and 65,000 flowers and plants a year (about 60,000 according to the city), sown from January. The Friends count more than 500 varieties of ornamental annuals and more than 100 tallgrass prairie species. According to their May 2024 article, pest control now relies on beneficial insects, among them lacewings, ladybugs and a whitefly parasitoid wasp, rather than chemicals.

The Noelridge Greenhouse can be visited on a self-guided basis on weekdays, at the corner of Council Street NE and Collins Road. The city also offers guided tours of about an hour, led by the Friends of Noelridge, which can include the landscaped beds and the butterfly tents. The main events are the Easter Showcase, the Mother's Day Showcase, with sales of plants grown on site, and "Lights & Blooms: A Tropical Holiday Adventure" in December.

Outdoors, Noelridge Park extends the visit: more than thirty beds, a hosta garden, a children's garden, an 8-acre prairie planted in 2017 and a monarch butterfly tent that releases hundreds of butterflies every year, according to the Friends. The gardens also include an All-America Selections display garden.