When is the Best Time to Plant Trees, Shrubs, and Perennials?
Spring and fall are the best times to plant your trees, shrubs, and perennial plants! One season is not necessarily better for planting than the other, as both seasons have their own pros and cons for planting. We are going to walk through the benefits of either season and talk about certain things that you should be aware of when planting either in the spring or in the fall.
Planting Trees, Shrubs, and Perennials in the Spring
Spring is perhaps one of the most popular seasons for planting. As soon as the snow begins to melt away and the sun starts to get warmer, many people start itching for greenery and can't help but cure their spring fever by getting some new plants in the ground. Here are some of the benefits of planting in the spring, as well as some struggles you may run into and other things you should be aware of.
Spring Planting Ensures a Long Growing Season
One of the biggest benefits of planting your trees, shrubs, and perennials in the spring is that it gives your plants a long growing season and plenty of time to establish strong roots so that it is prepared for the winter season. Spring planting also ensures that your new plant is in the ground before the intense heat of the summer sets in. The summer heat can add a lot of stress to new plantings, so getting your plants in the ground early can help avoid this unnecessary stressor.
Plant After the Last Frost but Before Temperatures Get too Hot
Timing your planting just perfectly can be a bit of a challenge sometimes. Planting while the ground is still frozen can lead to the roots of your plants freezing. Frozen soil is also very hard and the roots of your plant will have a difficult time becoming established where it is planted if its roots cannot penetrate the surrounding soil. Trees and more hardy shrubs can generally be planted earlier than perennial plants. Here in Colorado, the optimal timeframe for planting trees is from mid-March to mid-June. The average last frost date is usually around early to mid-May, so your tree will likely endure some frosty temps or snow, but it will be just fine. When planting perennials, on the other hand, you should definitely wait until after the threat of freezing temperatures has passed. Planting in May and June is recommended as this is generally late enough to avoid frosts and early enough to give your plants some time to grow before the summer heat takes over.
Be Careful of Late-Season Freezes and Heavy Spring Snows
As we said above, newly planted trees can tolerate freezing temperatures for short periods of time, while perennial plants may struggle. Here in Colorado, you never know what the weather is going to do. It can be 70 degrees one day and drop down to freezing temperatures the next. Same with snow. There have been plenty of occasions where the weather is warm and beautiful, and then out of nowhere a heavy spring snow drops overnight, covering everything in a foot of snow. The best thing you can do is try to hold off on the urge to plant your perennial plants until after the average last frost. And in the event that you plant your plants and freezing temperatures or heavy snow appears in the forecast, do your best to relieve the burden from your plants. Cover your perennials with buckets, cardboard boxes, or sheets to help keep frost off the leaves, and brush snow off the branches of your newly planted trees every couple of hours to prevent damage to the tender boughs. Worst case scenario, your plant does not make it, and in that case, you can consult one of our nursery professionals for details on your plant's warranty!
Water Lots Throughout the First Year of Growth
All new plant material requires very consistent watering throughout the first year of growth. Especially during the summer when temperatures are soaring, it will be SO important to water your plants 2-3 times per week, if not more. You will even want to water your newly planted trees, shrubs, and perennials throughout the winter if there is no snow on the ground. Even though your plants are in a dormant state throughout the winter season, our winters are dry and cold and lack of water can cause major damage to the roots of your plants. Learn more about winter watering in our blog, The Importance of Winter Watering.
Planting Trees, Shrubs, and Perennials in the Fall
Fall is also one of the best times out of the year for planting trees, shrubs, and perennials for a lot of reasons. However, there are some things you want to be aware of that are much different than spring planting.
When to Plant in the Fall
Similar to spring planting, what makes fall planting so great is that your plants do not have to try to establish strong roots while under the stress of the intense summer heat. Planting trees, shrubs, and perennials in the middle of the summer is typically not the best because you run the risk of your plant material experiencing heat stress. The summer heat causes plants to dry out in more ways than one, so plant when the summer heat has had a chance to die down! As every Colorado resident knows, the weather here is unpredictable, but the beginning of September generally marks the start of cooler weather. With fall planting, do your best to get your plants in the ground at least a month before the first hard frost. Since your trees and shrubs are going to be more frost tolerant, ideal planting usually falls somewhere between the beginning of September through mid-October. The first average frost date here in Colorado is usually around mid-October, which can be difficult for your perennial plants to withstand, so it is recommended to get them in the ground a bit earlier than your trees and shrubs.
The Fall Season Provides Ideal Soil Conditions
One of the major benefits of planting in the fall versus the spring is that the ground is already warm! Warm soil means soft soil, and if the ground is soft, this makes it easier for the plant to establish itself, as the roots don't have to work as hard to make their way through frozen soil. Soft soil also lessens your planting labor, as it will be easier to dig into the earth! The cooler day temperatures that fall brings also signals to the tree that it is time to put less energy towards foliage growth and more energy towards root growth, which is necessary for any plant to make it through the winter.
Root Growth is Encouraged
As we just mentioned, planting in the fall promotes well-established plant material because the combination of warm days and cool nights is ideal for stimulating strong and healthy root growth. Root growth is encouraged when air temperatures are cooler than the soil temperature. Trees and shrubs planted in the fall won’t have much noticeable foliage growth in the fall because they are instead diverting their energy toward establishing deep and healthy roots, which sets them up to be stronger plants in the spring. As we said above, it is best to plant trees and shrubs from the beginning of September until around mid-October because the roots of your plants need to grow for about 30 days before the soil temperature drops below 40 degrees. Your perennial plants will also need 30 days to grow before the first hard frost, so be sure to get them in the ground a bit earlier (around the beginning of September).
Mild Temperatures Means Low Transpiration
Apart from needing more water due to evaporation, plants also experience transpiration. Transpiration is essentially how trees sweat through their leaves. Trees release vapor through their leaves to cool down when it’s hot, and even though you can't see it, trees lose a lot of moisture this way! This can easily cause unnecessary stress to a newly planted tree or shrub, and it will also cause your plant to require a lot more water, which can prove to be costly. This is another reason why planting mid-summer is not the best idea. Plants that are established are more effective at absorbing and retaining water, which makes them able to handle the heat better than a new planting that is not yet established.
Protect Your Plants from Early Frosts and Heavy Snows
As we said above, frost and snow can be harmful to your newly planted trees, shrubs, or perennials. If freezing temperatures are forecasted much earlier than the average first frost date, it isn't a bad idea to cover any newly planted perennials. A premature frost could cause damage that may be hard to rebound from if the plant has not yet had a chance to establish itself. You will also want to be aware of heavy snows with your newly planted trees and shrubs. Their limbs are young and tender and may not be able to support the weight of a heavy snow. We recommend gently removing the snow from any tree branches or shrubs to keep the snow from damaging your plants. To learn more about how to protect your trees from snow, check out this blog!
Water Your Plants Throughout the Winter
While you may not think that it is necessary to water your plants throughout the winter, winter watering is essential, especially during dry seasons. Our winters in Colorado are historically dry and cold, and even though your plants are dormant, they still need hydration and a serious lack of water can cause irreparable damage. Learn more about The Importance of Winter Watering!
When is the Best Time to Plant Trees, Shrubs, and Perennial Plants?
If you have any questions on when to plant your trees, shrubs, or perennial plants, please reach out to us! And if you need guidance on how to properly plant any new plant material, check out our Tree & Shrub Planting Guide or contact us today. We are always more than happy to help with any of your planting endeavors and love nothing more than to see you and your plants be successful. Happy planting everyone!