Oh, Cold Snap.

Is Oh Snap too 90's? I can't tell. Anyway, Thursday night is the first night in my area that we will have below freezing temperatures. We're a little cushioned by the city warm zone but it was bound to happen sometime this month: a cold snap. I've been preparing some of my plants for the journey indoors. Others will be left out in the cold, but with some protection in place to make sure they don't freeze. Still others I'll let die off because they're annuals and aren't meant to live through the winter. 

What can survive a cold snap, and what should be brought indoors?
The Rosemary plant prefers above-freezing temperatures
so it will be brought in once it dips below around 35 F

The first to be brought in was my Angel Wing Begonia plant. As a tropical plant it doesn't like temperatures below 50 F and was starting to show signs of cold damage even at those temperatures. If the leaves start getting wilted edges or spots on them it might be a sign of the plant getting too cold. Bring the plant inside gradually if possible, starting by just bringing it in overnight and gradually decreasing the amount of outside time it gets until it is fully an indoor plant again. I have work so the least outside time I could get on a weekday was ~8.5 hrs, but I waited until a weekend and gave it two half-days before bringing it inside permanently. It seemed to do well. Now it lives under the grow light with the other begonias. Be sure to check plants for pests before putting them near your other plants. I got some aphid transfers, but luckily running the infested leaves under water worked to get rid of those.

Begonia living the warm life indoors.

Aloes and other succulents have a hard time in the cold if they are watered too much. They can easily get root rot since they go into a winter dormancy state where they are basically "asleep" and not absorbing much. The water then just sits in the soil and rots the plant's roots. Water your succulents less in winter even if they are indoor plants. If you would normally water as soon as the soil is completely dry then wait an extra week. The exceptions are tropical succulents like Jade and Hawarthias. They use the same amount of water year-round. I can usually tell it is a tropical succulent if it scorches in direct sunlight. Tropical ones for some reason require less sun, not more.

The aloe plant that spent a 40F day outside
but is coming in for the night.

Carnivorous plants that are native to North America like the Venus Fly Trap and some pitcher plants should stay in a cold-ish place for the winter to hibernate. However, they must not freeze. I'm experimenting with leaving my Venus Fly Trap close to the brick wall of my apartment, near the door to my porch. Hopefully this micro climate will keep it from freezing on all but the coldest nights in January and February, when it will be kept in the fridge until the temperature outside gets back around 30 F.

Side note: I did find out that the plant was dying, not hibernating so I switched it
into a better-draining and smaller pot. It is now growing some new
short, stubby winter leaves so I hope it makes it.
Also turns out there were five different plants in that cluster?! Two have survived.

My perennial plants stay outdoors for the most part. Tender herbs such as rosemary get pulled inside on freezing nights, others stay huddled together near the door. I put an old blanket over them on really really cold nights, but the columbine, oregano, chives, and mint have all survived strings of 15 F nights in containers on the porch, as long as they're next to the door with the blanket over them. Having a porch with a "ceiling" (aka: the second floor's porch) really helps with the cold too, as frost can never form all the way back at the back of the porch. The annuals I leave on the front of the porch freeze and die. I tried saving a basil plant indoors last year but by the end of winter it was sticks with a few sickly leaves attached. Basil is not meant to live more than one year. It flowers and self-seeds instead.

Sadly, lettuce does not do well below freezing either,
though some varieties are hardier than others.

If you don't have a south-facing brick wall to warm your potted plants against, another thing you can try is burying the pots up to the brim in the ground before the first frost. This acts like an insulator for the plant roots and will help the plant make it through the winter. The leaves will still die off, but they will come back in the spring if it's a perennial. Putting row covers over your plants can also help keep frost off and insulate the leaves. This is a way to grow hardy lettuces, kale, and brussel sprouts all winter long in our area. Row covers can come in plastic or a thin fabric which lets enough light in for the plants to keep going until spring. If only I had room for row covers on my porch! Fresh kale in February...mmm.

Plant huddle

I hope all of the perennials survive the winter and are ready to go once warmer weather arrives. The hardest part is not planting anything new until April!