Water Plants Outdoors In The Winter? Do You Really Have To?


Do you live where the ground doesn’t freeze in the winter?  Or at least does not stay frozen all winter? Where snow does not accumulate and stay?  Then watering your outdoor plants in the winter is something you need to think about.

These are the most common conditions that will need to watch for watering needs in the winter:

  • Containers
  • Newly planted trees, shrubs, perennials.
  • Evergreens
  • Areas coming out of a drought this past summer

When you water, slowly pool the water in the root zone area.  This is the area encircling the drip line of the plant if an established plant, or the root ball if newly planted.  The drip line is the area where rain would drip off and on to the ground if there was a light rain. 

Can you water plants when it’s cold outside?

Yes, you may not want to be outside watering when it is cold, but yes, you can water when it is cold.  Actually, depending on the circumstances, it may be necessary to water when it is cold.

How cold is too cold to water plants?

If it is below freezing, it is too cold to water.  It won’t do your plants any good if the ground or the soil in your container is already frozen. The plants won’t be able to uptake the water.  When the ground is frozen, the water can’t penetrate, as well as any that does will freeze almost immediately, making it unavailable to the plants.  Any water getting on the stems, leaves, or needles will just freeze too.  

You want to water your plants well before the ground has frozen.  This allows your plants to drink up before the water becomes unavailable, frozen water is not able to be absorbed by the root system.

Watering Hoses

 Also, there is the difficulty of hose management, cold hoses are notoriously difficult to maneuver when cold.  A quick tip is to keep any hose you will use this winter in a heated area, drained of water, between waterings.  For all other hoses, it is imperative the hose is drained of water to prevent water from freezing inside the hose, bursting, and damaging the hose. 

 In a heated area, well, just drain after any use anyway, you know you’ll be dripping water everywhere if you don’t.

After all this talk about giving plants enough water in the winter, it is just as important not to give your plants too much water in the winter.  Only give your plants water in the winter if the plants have not been in the ground long enough to become established, you do not get heavy snows, the temperature is near 40℉ or more AND the soil is dry to the touch.  If the soil is damp….DON’T WATER. 

 If your climate is not prone to drying out in the winter, don’t water.  This is completely climate dependant. Don’t overthink it. The folks who need to worry about watering plants in the ground during the winter, usually know it.  These areas are dry, windy, and do not get snow cover. If in doubt, stop by your local independent garden center or Extension service (Google it…if in the United States, you have one…).  They will tell you if it is a concern for you.

Water outdoor containers?

Watering outdoor containers is usually more of a concern.  Many folks that have outdoor containers have an automated system, which has been drained for the winter. Or water by hoses, which have been drained for the winter.  As well as the outside faucets may have been winterized against freezing. This means you may be left with your trusty watering can. It is lucky that most containers need a LOT LESS water in the winter.  

Check them once a week, and just before expecting a freeze.  If dry, and by dry, I mean even when putting your finger into the soil up to a knuckle you do not feel ANY moisture at all, then water deeply. Also, water deeply before a freeze.  Otherwise, the weekly checking will show a pattern to you of how often you will need water.  

Do not be surprised if only once a month.  But check it!

Don’t fertilize in the winter, wait until spring.

For the one thing that will ensure you pick the best plants for your conditions EVERY TIME, click here and read this!

How much water do trees need in the winter?

Trees, unless under unusual specialized circumstances, are usually fine after they are established.  Trees take a year per inch of tree caliper (diameter of the trunk about 6” up from the ground) to become established. Which means a tree that has a 2” caliper takes 2 years to become established on average. Other times you might want to consider winter irrigation is if you have very thick clay soils that will form deep cracks when dry.  These cracks will damage roots, irrigating just enough to prevent cracks will be helpful. On the other hand, very sandy soils that get very dry can benefit from watering. If the root dries out completely. There will be damage.  

For every 1’ in the caliper, 10 gallons at each needed watering is a good place to start.  These are the same rules that apply in the summer, just the amount of water and frequency of water is very much reduced.  Go outside, touch the soil. That will tell you what you need to know.

Do trees need water when dormant?

Trees need a small amount of water when dormant.  Just enough to care about the minimal amount of cellular activity to sustain it until it is time to grow again.  You can think about it like bears going into hibernation. Yes, they still breathe, yes their hearts still beat, but both are very slowed down.  Also, the SOIL needs to have enough water as not to pull away from the roots. That would let the roots dry out and cause damage.

Do evergreens need water in the winter?

The same factors apply to evergreens.  They are not quite in dormancy but are very slowed down.  Also, the leaves and/or needles remaining lose moisture to the drying winds.  This moisture needs to be replenished. Plants that are native to your area have developed to withstand your winter conditions.  Whether they are cold and wet, cold and dry, warm and dry…. If you have planted non-natives, they might need a bit of a helping hand to thrive.

Related Questions:

Can watering plants prevent frost damage?

There are some very specific reasons why you would want to water during freezing weather, but these are not always to irrigate a dry plant.  Yes, watering thoroughly before a freeze is important. All the way from the cells, up to the whole plant. Overhead constant sprinklers during the night, usually the hour or two just before dawn (being the coldest) is a method to prevent damage to, usually the flowers, when a frost or light freeze is expected, and just a degree or two of protection is all that is needed to prevent the flowers being killed by the frost.  Row covers are very effective for this but can be difficult to use on tall trees or large crop areas, so this solution is most often used in agricultural crops such as strawberry production or citrus tree production. How does this work? As water freezes, it releases heat. Just enough that as the water is freezing, the temperature stays at freezing. The temperatures do not dip below, so as long as the water is still in the process of freezing, the flower bud that the water is freezing onto will not drop below freezing.  This is usually just enough to get the crop through a frost without damage. Pretty neat. Science.

Do dormant trees need sunlight?

Trees that are fully dormant without leaves do not need light.  The light is for photosynthesis. No leaves, no photosynthesis. Now an evergreen that keeps its leaves/needles DOES need light, even during the winter when they are not making active above-ground growth.

How can you tell if a tree is dormant?

If a plant looks dead, but the root system is healthy, then it is dormant.  This is easy to see if it is a potted plant that you can knock out of its pot and see white healthy roots.  For a plant you can’t do that too, try the scratch test. Scratch the bark, if it is dry and brown. That section is dead.  Keep moving further down the tree or plant, closer to the soil, and try again. If you get all the way down to the soil, and are still dry and brown.  That plant is not dormant, but dead Only chance is it may sprout from its roots in the spring.

What is the best way to drain a hose before a freeze?

I find the easiest way to drain a hose is first, take off any hose end nozzle.  Next, detach from your faucet. Then while it is still stretched out where you used it, start lifting at the side that is at the highest grade, higher elevation, and put over your shoulder and walk towards the other end of the hose, running the hose along over your shoulder as you do.  Keep in mind, your shoulder will get any of the dirt on the hose, transferred to your shoulder… Do this all the way down the length of the hose. Any moisture left in the hose at this point will just be a shell of frost, like what is on your windshield in the morning, on the inside of your hose.  

This brings us to the point.  When using your hose for the first time after the winter, leave the hose sprayer end off and flush any ice crystals and/or debris from the hose first.  This way it won’t clog your sprayer.

Happy winter watering 🙂



Toni

Toni has a bachelor degree in Plant & Soil Science, has lived, gardened and growing all over the US, in Vermont, Tennessee, Idaho, coastal North Carolina and Virginia. She has been sharing her knowledge through writing, one on one consulting and talking to anyone who wants to listen at social gatherings everywhere : )

Recent Posts