Those leaves will contribute nutrients to the soil sooner than would cedar simply because the Soil Food Web will digest them quicker.

Yes I know , but this doesn't answer my question. Is there any difference between cedar mulch and leaf mulch in terms of nutritional benefits. ın other words, is one richer in nutrients than the other?

When you say cedar mulch do you mean bark (fines), mulch made from the wood, or from small branches with 'leaves' (needles? What are they called?). Personally I think unless you know which specific nutrients you need, the question doesn't make much sense. Kimmq is on the right track, healthy soil more the question than 'more nutrients'; maybe you have enough nutrients (which ones?) already

If we're talking about shredded cedar wood you can buy in a bag, I would say leaves probably have more nutrients, just to answer the original question. I agree with all the above though.

toxcrusadr, yes I meant commercial sold shredded cedar wood mulch. If you agree with other commentators, do you think it's worth the hassle of gathering leaves and mulch the rose plants, or should I just add cedar mulch (which last much longer)? I use shredded leaf mulch for the vegetable beds, but I'm debating whether I should use it for the rose plants, too.

The mulch is not intended to "feed" or fertilize the plants so its specific nutrient value is really of no concern. Neither the cedar nor the leaf mulch will eliminate a need to fertilize as well, should the plants require it, so use whichever mulch works well for you and is easily obtainable. That should be the overriding factor......not how much of a nutrient load they may have!!

That said, if your soil is of poor texture or low in organic matter, degradable mulches are a great way to improve it, without digging it up, which you can't do around roses. So even though its NPK contribution is relatively low, there are other advantages. All depends on what you're dealing with.

Something I read somewhere a few days ago: Tree leaves contain minerals which the tree roots obtain from depths of the soil that are lower than the roots of other types of plants, and because of this, fallen leaves add important nutrients to your soil. I do not know whether tree leaves contain more "nutrients" than the woody material of the soil. My belief is that using mulch which decays faster is preferable to using mulch that decays slower, provided that you have the time and wherewithal to do the replenishing.

This is pure supposition, but it seems to me that if nothing else, leaves have less carbon mass than wood and therefore have more concentrations of nutrients/minerals per volume and mass than wood. And, as ellatiarella brings out, the decomp rate of leaves is much faster than wood. I agree that while decomposed woody material has benefits ( I use a lot of it myself,) leaves are preferable for both nutrients and turn around time for reentering the soil web. In fact, even in nature the slow decomp of wood benefits carbon sequestration, while the faster decomp of leaves (and more delicate biomass - including grasses and other less durable plant growth) is much more responsible for playing a role in the creation of creating nutrient-rich topsoil.

That said... it's also true that any nutrient benefits of composts and mulches are long-term at best. They are not, in themselves, a replacement for situations where fertilizers are needed for optimum plant health.