Read this: https://female-orgasm-denial.tumblr.com/post/157703040274/cucumbers-the-disposable-dildo-of-choice-for (it includes an old guy talking about condoms, it’s awesome).
Without condoms it’s not ideal, as it may have been grown with pesticides and we don’t want those in you. BUT at a push, cleaning it really well will deal with most of that (after all we do EAT the damn things).
DO NOT use the plastic wrap that comes on cucumbers from the store, it will CUT you and it’s no cleaner.
Have you thought about condom alternatives though, remember we aren’t having to stop babies being made here (cucumber babies are only a myth:)
You can use a latex medical glove or a balloon over it. I wouldn’t recommend a normal plastic bag though, they are as likely to be contaminated and also they way they fold up on it could hurt you. A shower cap might work too.
However, all that aside I’d recommend other DIY toys before any vegetables, check out my DIY sex toys tag for plenty of ideas.
And to finish:
Got a DIY sex toy story to share? Send it in! (seriously people love them) and always feel free to ask sex ed questions