Diane,
I have known experience with pine needles in a vegetable garden; but I’ve used oak, maple, willow, and fruit leaves in many combinations for years. Yes, the oak will take longer to break down; but you can help that by either picking them up by mowing or using a leaf vacuum too break the leaves. smaller pieces and broken edges will really hasten the decay of all your leaves. That’s not a problem with a garden where you should be repeating that mulching yearly.

Hi, Joanie. This makes no sense whatsoever to me. First: garden peas (edible varieties of Pisum sativum) are mostly self-pollinating, and have both male and female parts inside their flowers to make this possible. Bees can get in sometimes if the flowers are open…but the flower structure isn’t very welcoming to them, so it’s not what the plant relies on for pollination. Second, so-called sweet peas grown as cut flowers are in the same family, the legumes, but in a different genus altogether (Lathyrus, specifically L. odoratus). Plants of different species (let alone different genera) are by definition not closely enough related to cross-pollinate. So I think not. Wonder where your friend ran into this idea — almost a superstitious notion, and I suspect one that arose from the internet.