First, your rhubarb plants can be divided in early spring but I suggest you wait until late February or early March just in case a winter storm freezes the soil. Second, Your blueberry plant can be trimmed up anytime of year so go ahead and shorten any branches that are too long or crossing. Third, You can remove the volunteer plants from your Raspberry Shortcake plant now and this will not impede the flowering of the main plant. You can also wait another month to remove the extra plants. As long as you perform the surgery at least a few weeks before the plant flowers it won' t mind at all. Keep growing, Marianne Binetti