The cactus is frozen soft outdoors, can it still be revived? If so, what can I do?

You can judge with your eyes. If the stems have been completely frozen to the point of being transparent, water will come out when you pinch them with your hands, or if they are directly sunken inward, and the stem tissue is as soft as a roasted sweet potato, it must be alive. If it doesn't work anymore, you can only pull it out and throw it away.

On the other hand, if most of the cactus stems are still strong and only a small part of the top is frozen, it can still survive. We can move it indoors to a room temperature environment for a while. After about 3-5 days, cut off the frozen parts and apply carbendazim. When the temperature rises in spring, new shoots will sprout again.

Extended information:

If you are in the Northeast or Northwest, cactus will basically not survive if left outside for one night in winter, because few cacti can withstand minus 20-30℃ At a low temperature of about 100 degrees Celsius (very few exotic varieties can), they will be frozen directly into a puddle of "soft mud".

Under normal circumstances, the common cactus with yellow flowers that we usually see is fine even if the temperature is as low as minus 5-10 degrees Celsius. Repair will only leave some scars at most.

Of course, the fact that cactus is frost-resistant does not mean that all cactus plants are frost-resistant. We must make this clear. Do not leave cactus, cactus, etc. outside to freeze, otherwise they will Directly frozen to death.