Winter continues to support cold temperatures and lower amounts of daylight. Each of these factors contributes to putting stress on both indoor and outdoor plants. Of course most of the outdoor plants are dormant right now so it doesn’t matter, but winter damage can occur in very cold winters with a lack of snow.
If the temperature does get into the upper 30s, you can still apply an anti-desiccant to your broadleaf evergreens such as rhododendron and hollies to help protect them from losing too much moisture. As we get deeper into winter and start headed to spring, the sun will become strong enough to start doing some damage to the plants that are susceptible to this type of damage.
Now, if you have had a plant in the ground for years and it’s had no problem, you don’t need to worry about it, but those plants which are newer or haven’t been through several winters yet would benefit from some winter protection.
Too much or too little water is the most common mistake we all make with our houseplants. In the winter nearly all of our plants will need less water. If you keep watering them at the same rate you did back in September the plant won’t be able to keep using all the water you are giving it and eventually the soil will become saturated and root rot will follow. If your plants are in a sunny and very dry environment and in a clay pot, the soil might dry out very quickly if the heat in your house is up high. In this case give them more regular water so the soil doesn’t dry out.
It might not seem possible, but you can get insects inside during the winter even easier than in the summer. The warm and dry environments we create inside are perfect breeding grounds for spider mites, aphids and scales, three of the most common problems facing indoor houseplants. I like to use a horticultural oil on my plants midway through winter to keep any insect problems at bay. If it’s too cold to bring the plant outside you can always treat them in a garage or on a porch. Don’t worry if the temperature is 35F, as long as it’s not freezing the plant will be ok for the limited amount of time you will have it out there. I have brought my plants outside in the snow in February on a sunny day when it’s hit 40F and sprayed them without any issues from the cold.
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