As part of our "Question of the week" feature in our email newsletter we recently tackled the question: So the plants I wanted to bring indoors got a little frost... will they be okay? 

Here is the info:

[Originally published October 13, 2016 ]

This week many local gardeners got our first taste of real frost... about 20 days past that average first frost date so that is pretty good! However it may also mean that plants intended for wintering indoors got a real taste of cold weather. Often houseplant-y selections such as rosemary, bay leaf, myrtle, geraniums, jasmine, sages and many others look none-worse-the-wear after initial exposure to frost; however trouble often starts to show up a little while after coming inside. Here are some easy ways to give your late-movers the best odds of success indoors:

1) Water plants deeply as they come indoors. This means ensuring the whole root system is hydrated while also being sure that the roots don't sit soggy (be sure pots have drainage). Allow the soil to dry to the touch be fore you water again - but the key point is that the entire root ball gets moisture (it is actually pretty easy to inadvertently only water a portion of the roots on larger pots which leads to extra stress for plants moving inside).

2) Make the transition as gradual as possible. Plants that have had cool nights or frost respond poorly to suddenly ending up next to heat vents or cozy indoor spaces. If possible first put plants in a cooler location indoors such as a three season sun room or in front of patio doors. Give them a couple of days in progressively warmer locations.

3) Cut plants back. Late movers are very likely to shed... a lot! This can be preempted by proactively cutting the plant back. For plants that have a leafy character the pruning can be dramatic. For woody selections - such as hibiscus or myrtle - the focus is on cutting back stem tips. There is still likely to be some shedding but pruning stimulates new growth which has only known the warmer indoor conditions.

4) Apply a fermented potassium fertilizer such as Evolve Rage Plus. Potassium plays a remarkable role in reducing the effects of various stressors in plants; empirically identified benefits include increasing resistance to pests and disease pathogens, increased tolerance for drought stress, and increasing plants' ability to remain metabolically active under bellow optimal temperatures. Fermented potassium fertilizers not only have the benefits of K nutrient but also all of the beneficial enzymes that occur via fermentation.

5) Avoid repotting or applying a general purpose fertilizer until plants have stabilized indoors. It may take a few weeks (say 4 - 6 weeks) as plants adjust and start to kick back into gear indoors.

6) If plants are high-light oriented they will benefit from full spectrum grow lights. For taller plants the easiest solution is to use 13w full spectrum CFL's that can be put into a multi-headed lamp and shine light onto different levels of the plant. For shorter plants T5 tube fixtures are extremely effective.

Many of the above points are helpful even if plants were moved indoors before this week's frost as well; let us know how your houseplant move is going!