Perhaps the light that you planned for isn't coming through because of a tree that has fully leafed out. Perhaps your perennial has outgrown its current location. Whatever your motivation, transplanting existing garden plants can be stressful. Taking a few extra steps can set you up for success though.
Hot temperatures can be deadly for transplanting, but if you must transplant, do so during the early evening hours. Doing so allows your plants the best opportunity to take to their new surroundings without the added stress of summer heat.
Using a hand shovel, dig a ring around the base of the root, with a circumference wide enough to allow you to get under the root ball as cleanly as possible. Digging at least 6 inches down for larger plants, use a larger shovel to dig up the root ball, careful not to shake off any attached soil.
Once the plants have been uprooted, it's a race against time. A best practice is to dig and pre-saturated the new location ahead of time, but regardless the plants need to be in their new location as soon as possible.
Once you've found a designated new location, water that area thoroughly the day prior. The moist soil will be a welcomed environment for the plant. Additionally, watering the plant in its current location will help with digging on moving day. From there on, water once to twice per day depending on temperatures and sunlight.
