Boxwood - indoors or not indoors?

[j evans]

Mine just stay outside year around. Winter is spent with alk the other plants, sunk in mulch behind the garage.

 

[WNC Bonsai]

This is a confusing topic since as pointed out, the internet can be a veritable fountain of misinformation. The main consideratin is knowing the conditions the plants can take, most importantly the minimum hardiness zone. Common boxwood (B. sempervirens) is good to zone 5 whereas Kingsville (B. microphylla) is a zone 6 plant. If you follow the 2 zone rule of thumb for bonsai in pots then these plants are only good down to zones 7 and 8 respectively. Therefore because I am in zone 7 I can have several large common boxwood in the landscape but my Kingsville goes in the garage each winter.

To complicate things even more it is possible for varieties within a species to pop up with more or less cold hardiness, its called genetics. Unless you know that your plants can take more or less, you have to go with the published literature on these. There are some good resources on the internet such as the Missouri Bontanical Gardens and various horticultural groups that provide excellent plant care information, but remember that it is mainly for plants in the ground not in pots.

 

[Bonsai Nut]

The main consideratin is knowing the conditions the plants can take

What is funny is that in most parts of the countries people are concerned about how much cold their plants can take. I worry about how much cold my plants need.

Many tree species need winter to some extent or other. I spend a lot of time trying to find cultivars that don't have high cold requirements. In the case of stone fruits like peaches, the cultivars come with a very specific "freezing degree days" requirement right on the label. If I don't have a cold winter, my stone fruits don't fruit. But with bonsai, if I don't have a cold winter, some of my deciduous - Japanese maples, trident maples, Japanese hornbeam, etc - might die. I spend winter trying to keep my trees cold. I don't have a ton of true tropicals.

 

[WNC Bonsai]

What is funny is that in most parts of the countries people are concerned about how much cold their plants can take. I worry about how much cold my plants need.

Many tree species need winter to some extent or other. I spend a lot of time trying to find cultivars that don't have high cold requirements. In the case of stone fruits like peaches, the cultivars come with a very specific "freezing degree days" requirement right on the label. If I don't have a cold winter, my stone fruits don't fruit. But with bonsai, if I don't have a cold winter, some of my deciduous - Japanese maples, trident maples, Japanese hornbeam, etc - might die. I spend winter trying to keep my trees cold. I don't have a ton of true tropicals.

Very good point. Because of increased climatic variability I am constantly concerned that mid-winter warm spells will cause my maples to pop early followed by a deep freeze whick kills new growth. Some trees such as larch and other plants from low temperature zones may require constant cold throughout the winter to keep them healthy. Right now these plants are sheltered under a thick layer of leaf mulch and nestled among large conifers to buffer them from wind and temperature fluctuations. However I am considering digging into a hillside and buidling an insulated cold storage bunker like my grandfather’s old root cellar. I also may need to make room in the spare refrigerator in the basement!

 

[Melospiza]

I just thought this was an interesting quote from someone who only had 16 posts and hasn't been here since 2014.

I assume this is the end of his super-expensive and extremely "scientific" experiment to prove everyone wrong. More and more I am learning that, if you are constantly fussing over the day-to-day life of your trees, you are likely doing something wrong.