Trying to move a large cactus to a new location? Try these tips to avoid damaging your plant
The worst time to transplant a cactus is after it rains. The best time to transplant a cactus is after it rains. Rain does something to our cactus in the desert. It puts a relatively huge amount of water into the root zone all at once. When it rains that water gets sucked up quickly, which is one strategy for taking advantage of scant rainfall. But when there's a lot of water they keep sucking and some will actually split at the seams.
Dehydration solves the weight problem when transplanting cactus. This isn't about small cacti in patio pots but big columnars like the multi-stemmed cousins of the famous fence-post cactus. With water itself weighting eight pounds per gallon, these big fellows suck up an incredible amount overall. making them double in weight from the time of summertime dehydration.
After rains, the inside of a Peruvian apple cactus is a lot like a fresh garden cucumber. The water pressure inside is significant; the outer epidermal layers aren't accustomed to it stretched to the max. A hard bump against the stem or failure to support the entire length of the stem when handling will inevitably cause it to break off. This can spoil a nice specimen.
When working with Clark Moorten I saw a curious rig I call a "cactus dolly" built by his late father, "Cactus Slim" Moorten. Slim took a two-wheeled vintage concrete wheelbarrow and extended the handles with pipes. On top of that he attached a long narrow platform covered with dense carpeting that extended well beyond the front of the barrow. This was long enough to support a typical fence post cactus up to eight or ten feet long.
Two big Model T wheels allowed him to tip it on a fulcrum downward to the ground at the base of the plant that had been excavated. The cactus was gently was tipped over onto the carpeted surface that took all the weight. With roots free, clear and hanging in the air out front, the wheelbarrow was tipped back down to proper handle level, then pushed to the new location. When the new hole is ready, the root ball is tipped back down so it sits directly into the hole where it's easy to stand up again.
This old idea demonstrates that Slim and Clark moved some really big plants and did it with great success. They also knew that digging out a big cactus for transplantation after a long dry spell made the excavation difficult and dangerous to the stems in areas of soil compaction.
Hardpan is not a soil type but a weird thing soils do here. It involves minerals that combine with water to cement sand particles into brick-like consistency. Even if broken up, once wetted, the old reactions begin again to harden that ground and resist water absorption. It's another reason cactus often lack deep roots due to hardpan restriction underground.
The hard ground is a horticultural concern due to plants easily damaged when extracting their often frail roots from the earth. Damage is permanent and unsightly and must always be avoided. Although the plant is as light weight as it will ever be, the breaking up of ground often riddled with rocks requires a pry bar and a strong back.
The most important thing though, is to recycle some good free carpet remnants. With tall cacti, it's much easier if you wrap the cactus in carpet with the soft side in, then tie it with twine to keep the tender skin protected. It also allows you to grasp and hold the plant while you're digging it out so you don't get stabbed in the process. Leave the carpeting in place until you're ready to store the plant in shade. This is the time to dehydrate a wet one and allow all the root tears and punctures to thoroughly dry out before reintroducing to soil-born organisms.
Cacti are among the easiest group to transplant, but larger individuals can be dangerous and challenging. Be sure to mark the south side of your cactus before removal, and reorient it exactly the same way in the new spot. And always take note of the last time it rained to know when digging is easy and or exceptionally hard.
Maureen Gilmer has written over 20 books and hundreds of articles on California gardening, plants and the environment. Her upcoming book, "Living With Wildfire," is a consumer's guide to better understand and prepare for these growing natural disasters. Contact her at: firstname.lastname@example.org, (760) 363-1144, P.O. Box 891, Morongo Valley, CA, 92256.