Hostas are such a wonderful plant to have in the garden because, for the majority of the time, they require very little upkeep and are perfectly happy to be left to grow on their own.
One thing that is important to look out for in your hostas is reversions. This can only happen to variegated or streaked varieties and is when one shoot or more appears as one solid colour (usually green or blue). Unfortunately, there are some varieties that may need more attention than others in this regard as they are more liable to reverting.
What Should I Do If My Hosta is Reverting?
If you have a hosta that is starting to revert, its important not to leave it and hope that it will resolve on its own. Reversions may start as one shoot, but can quickly start to overwhelm the rest of the plant and leave you with a fully reverted plant. Generally the solid colour reversions are larger, faster growing and more robust than the original variegated or streaked variety, so they can quickly overtake them for space.
When you see that one of your hostas is starting to revert, you need to divide out the reversion as quickly as possible. If left, there will be a large portion of the plant that will need to be removed in order to keep the variegation or streaking. Use a knife or spade to cut them away. Don't just cut the leaves off because the root beneath will need to be removed, this contains the information about the plant such as leaf colour.
If your plant has completely reverted, it is unlikely that the variegation or streaking will return. A lot of the time, you will be able to find out what the reversion is if you know what the original plant is named; Hosta 'June' reverts to 'Halcyon' for example. Some reversion are culled as they may not be very interesting, but some have been given names of their own and become popular varieties in their own right overtime like 'Plug Nickel' which is the all green reversion of 'Cracker Crumbs' and 'Second Wind' which is an all green reversion of 'Whirlwind'.