So you are having some mana issues in Heroics ey? Well I aim to give you a few tips today to help lessen your healing burden and improve your HPS while lowering mana costs.
Right now early in the expansion ALL healers are very gear dependent and have mana issues since players HP pools have tripled or even quadruple while our healing spells heal relatively the same as they did in WOTLK but with higher mana costs.
How do we combat this with an efficient rotation? Below is a comprehensive "what to do list" for most circumstances you will encounter in Cata heroics.
High single target damage (Tank) - 3xLifebloom + Nourish Spam this will keep him going and when the damage spikes its much better to throw a rejuv (with the 15 percent hp instant talent) and a swiftmend down on him right then and there instead of a regrowth or a healing touch. If it is necessary to do a larger heal you will want to still do a swiftmend if its available just for some cushion. Try to only use regrowth on clearcast procs!
Low multi target damage - Wildgrowth + Group up swiftmend + nourish this is as efficient group healing as you can get and you can do it often. Its much more efficient then blanketing the group in rejuv since its a fairly large cost now. Dont underestimate the aoe from a talented swiftmend its strong and in conjunction with wild and nourish should be extremely mana efficient for you.
HIGH multi target damage - TOL + LB Spam + swiftmend + Wildgrowth + Clearcast regrowths this will be EXTREMELY mana efficient for you. The trick is to know when the high damage is going to come and be ready with your TOL that obviously just comes with some practice and experience. Since TOL lets you use LB on multiple targets you can cast it on your entire group multiple times (I usually cycle) while swiftmending and hitting wildgrowth. It may be tempting to use regrowth a lot while in TOL form since its instant but dont! Only use it on clearcast procs which you should be getting lots of due to casting LB on multiple targets constantly. I cannot stress how efficient this is for healing. Only stop to nourish when swiftmend is on cd and someone NEEDS a heal! Your LB spam will get you those free instant regrowths which if glyphed should refresh automatically if the target is below 25 percent hp.
Reforging -
The easiest way to increase your heal time is to reforge any piece that doesn't have spirit to spirit. I prioritize reforging mastery to spirit and typically I do not touch an int piece which has haste and crit since both of those are very very vital to resto druids. Once you are haste capped you can reforge haste but pretty much mastery gets the boot for Spirit! If your spirit is high enough your nourish essentially becomes free to use always.
Of course as always dont use innervate when you only have 2k mana! I typically use it midway through my mana pool. I am also an alchemist so using wotlk mana pot helps to even if its a low mana amount. Using other mana pots are of course recommended if you arent one.
Ill update this if anyone has some additional healing tips.