Before you bring your Pelargoniums out of storage, make sure you have at hand all the supplies you will need. Of course, you will need potting mix, empty pots, and scissors or pruners. You may want a tarp or some other type of throw for your work space as prepping the Pelargoniums for potting can get messy. If you have labeled your plants, be sure to have some way to label them once they are in their pots. I personally don't label my plants because I like the surprise when they bloom again!
Here is what my plants look like just before I bring them out of storage.You can see some of them already have new growth.
I like to use a large plastic bin or tub to take my plants upstairs to my work space. The foliage has become dry and brittle so it crumbles and makes a mess when you move the plants. I inspect each of the plants and sort them into piles based on how healthy they look and what size pots I expect to pot them up into.
These two look nice and healthy and should bounce back quickly. I often will cut off that pale new growth.
These don't necessarily look vigorous, but they do show new growth, so they should be fine. Keep in mind that the new growth is at the tips and will get cut off in my method, but the new growth shows me that the plant is still viable.
Some may appear very desiccated with no sign of green, but this does not necessarily mean they will not grow. I look to see whether the trunk just above the roots is still plump. I may select four or five like this to keep, just for the thrill of seeing one or two come back to life. If you have limited space or way more Pelargoniums than you need anyway, you might just discard them.
Ok, so it is time to start potting. I strip off all the dry dead material from all the stems so that I can get a good look at what I have to work with. I cut back each plant to one to three inches, depending on its health. I want to see green in the stem. If it is dry and brown, I cut back farther. I pull off any old dry potting mix from the roots and I trim the roots back to about one inch if they have not already broken off when I pulled off the remaining soil. In order to give the future new growth a pleasing shape, I may also cut off some stems even if they are healthy.
Here is an example of one I will discard because there is no green to be found in the stem and the trunk is not particularly healthy.
Here is where I have cut back to green. The second picture shows on the left where this first cut was made, and I will make the next cut just above where a new leaf is forming and where the stem is turning brown.
Here is one of the healthiest selections before and after trimming.
Finally, here is one that has no green in the stems, but it has a nice-looking trunk, so I will pot it up and see what happens.
As I pot up each plant, I give them a very healthy watering. I put them on a shelving unit that I can easily move around to take advantage of the maximum amount of sunlight in the room where they wait until it is finally time to move outside.
Remember, not every single plant will make it. Sometimes one that appears healthy in the beginning will just wither away. Some will bounce back faster than others. I find that is part of the fun and wonder of nature.