Although both are used, the more common and more correct English word for wild-growing plants with conspicuous flowers is "wildflowers" and not "wild flowers". Whoever created the online language translation services (Babel Fish, Google Translate, etc.) obviously did not know this and the word "wildflowers" will not translate but "wild flowers" will.
Spring wildflowers in Tucson's Sabino Canyon.
My websites, especially my Wildflowers of Tucson, Arizona website, get a fair number of non-English-speaking visitors (many from Mexico) who use online translation services, and it is annoying that the most common word used on my site won't translate for them. Even more annoying are the attempted translations of the Latin scientific names. I wish that there was a "do not translate" html tag for scientific names!
Interestingly, the Spanish word for wildflowers is "flores silvestres", but the separate words "wild flowers" translate with online translators as "flores salvajes". Oh dear, more multiple word confusion as I see that both are used, although "flores silvestres" is far more common.