Colorado Plant Care Guide

Studies have shown that wood and bark mulch can almost double a trees or shrubs growth in the first couple of seasons after planting. Each tree should have a circle of mulch that covers the area needed to dig the hole. In more idea situations the mulch can cover up to 4 times the area of the hole.

While trees are trying to establish, weeds often compete with the limited water supplied to most establishing trees. Removing weeds and grass around the newly planted tree is necessary for the plants healthy transition and survival. Using mulch will help a great deal in keeping weeds under control around the base of your trees. Organic mulches have the advantage of adding much needed organic matter to the soil.

Where to place it:

Apply a 3″ thick (after settling) layer of mulch to at least an eight-foot diameter circle around the plant, or maintain the area weed free with herbicides, to help discourage weeds and turf. This area should be maintained during the establishment period at least two feet in diameter (preferable three feet) for each inch of tree trunk diameter (to encourage rapid establishment, minimum diameter should be eight feet for trees with a trunk diameter less than 3 inches). Apply a thinner layer of mulch over the root ball, for aesthetic reasons if you wish, but keep it at least 12 inches from the trunk (24″ diameter mulch-free area) so the trunk bark can dry. This also allows rainwater, irrigation, and air to easily enter the root ball since it does not have to drain through the mulch. Applying too thick a layer can kill the plant by holding water meant for the roots, oxygen starvation, death of bark, stem and root diseases, prevention of hardening off for winter, vole and other rodent damage to trunk, keeping the root ball too wet, encouraging formation of stem girdling roots, and repelling water if the mulch dries out.

Potential benefits of mulch:

Once the tree is well established in the landscape, it is best for the tree to maintain mulch under the drip-line of the tree – no turf under the tree. Some managers reduce the size of the mulched area, but soil can become compacted under the canopy from mowing equipment causing serious damage to the tree in some circumstances. Arborists, botanical gardens, and landscape managers are beginning to realize that trees are much easier to maintain in good health when the soil beneath the canopy is mulched. This probably results from a healthy microbial, earthworm, and insect population and good air penetration into the soil. Within about a year after applying mulch under the canopy, you can feel the soil becoming softer. Roots grow rapidly in soft soil, slowly in compacted soil.

Types of mulch:

Composted yard waste makes great mulch and may suppress Phytophthora and Armillaria infection in some circumstances. There are a growing number of examples around the US of applying fresh wood chips or bark under the canopy of landscape trees. Landscape managers report that these trees remain healthy and in some circumstances health is improved. Applications of fertilizer have been reduced or in certain cases eliminated in some of these landscapes. Fresh (not composted) wood chips could, in some circumstances, enhance pathogens such as Fusarium and shot gun fungi. If you suspect that this could be a problem in your region, apply it to areas that already have some mulch on the soil. Since non-organic mulches, such as rubber or lava rock, add nothing to the soil they may be less desirable than organic mulches. However, synthetic mulches may have applications where organic mulches might blow or wash away.

Sunlight and wind can really effect the area in which certain trees can and cannot thrive. The following will highlight how to choose the best plants for your specific exposures. We will also detail what to look for and what to explain to our staff when picking the perfect plant.

Sunlight Concerns:
  • Typically in Colorado an area with morning sun and afternoon shade is one of the safest areas to plant.
  • Areas in Colorado with morning shade and afternoon sun provide the least protection.
  • In Colorado most plants that say they require full sun can still do great in a partial shade environment. Colorado’s sun is very intense due to our elevation and most of the time our part shade is like most states full sun.
Time of Day:

The time of the day that your plant receives sunlight can also be a factor when making your plant selections. Indirect light and heat is also an issue and should be looked at with a similar concern as direct sunlight.


When picking your plant you must take wind into consideration. The summer wind is one thing but winter wind is usually much worse and can kill plants that otherwise would live. Typically the safest area to install a delicate plant is on the north-east side of your home or wall. Walls can be hedges of evergreens, fences, neighbor’s homes,  and many more permanent objects. Some plants that do not like wind are Yews, Boxwood, and Japanese Maples. These are best planted in shaded areas as well.


Late spring and early fall snows can destroy trees in Colorado. Please be sure to stake your trees to prevent the smaller ones from bending to far over or braking. You should also be ready to shake off the trees branches in the middle of the night to prevent the build up of snow on weak areas of the tree. By simple wiggling the tree a few times with a broom during the snow fall you can prevent thousands in damage.

Be Creative:

If you are among the many that want a special delicate tree or shrub but don’t have the perfect place then why not make one. By planting various trees and shrubs that can handle full exposure you will create a safe haven for the most delicate of plants. We can help you pick trees and shrubs that will create partial shade and full shade areas or walls to create that private oasis you have been waiting for. When you come to CreekSide we never expect you to know the exact plant you want all we need is for you to give us some idea of what you want to accomplish with your future plants. Then with some simple questions about your planting location and its surroundings we can help you pick the perfect specimen.

Protection from rodents:

Plastic PVC protection tubes, paper wrap, wire mesh or thick cardboard can protect newly planted small trees from rodents, deer and sunscald.

Protection from climatic extremes:

Wraps tightly secured to the trunk provide little buffering of climatic extremes. Burlap and plastic devices are occasionally used as wraps.

The most commonly used material, paper wrap, does not buffer temperatures as presumed (Litzow and Pellet 1983). There is little research that has validated the practice of wrapping or spraying the trunk to prevent sunscald. Trunk wrap most often does little harm to the tree provided it remains intact in winter and is removed the following spring along with any tape and string used to tie it on the trunk. Use biodegradable material if possible.

What is Sunscald?

Sunscald on the south and southwest side of the trunk of thin-barked trees has been attributed more to lack of soil moisture following transplanting than to any other cause (Roppolo and Miller 2001). Injury commonly described as sunscald can have a variety of causes including trunk cracks resulting from improper pruning cuts, canker-forming fungi, and boring insects. Preventing sunscald may be as simple as irrigating regularly following planting and making appropriate pruning cuts.

Splits (so-called frost cracks or sunscald) along the lower trunk have also been associated with under-irrigation after planting. Since most root growth occurs in the summer months, irrigation during this time is crucial. You could lose almost an entire year’s root growth if you under-irrigate in the first summer.

Protection from equipment:

Trunk injury from equipment causes serious and lasting damage to trees. Regular weed control in an eight foot diameter circle around the trunk is the best way to protect the trunk of a recently planted tree. This will help ensure that equipment stays clear of the trunk.

Wood or metal stakes can serve to protect the tree from accidental injury from lawn maintenance equipment. Three or more stakes can be driven through the mulch layer into the ground several feet from the trunk. Do not attach them to the tree. Mowers can bump into the stake but not the tree. Thick, black plastic drain pipe slipped around the base of the trunk or other plastic devices are also used to provide some protection against string trimmers and mowers.

In Conclusion:

Trees with thin bark can be damaged by warm winter sun and should be protected in most cases. However, it needs to be said that wrapping a tree is never mandatory and each situation should be determined on an individual basis. You must take in to account the location you are planting the tree in, the trees winter exposure, and the variety of tree. I have seen plenty of cases where a tree was damaged by not removing the wrap. Please pay attention and wrap with caution.

Fertilization can be very complicated and difficult to understand. Sometimes this word is over used or used as a catch-all to mean feeding you plants. We recommend consulting with one of our staff members before choosing a fertilizer, root stimulator, or other method of enhancing your plants growth.

In many cases it is not recommended by CreekSide to fertilize your plants at the time of planting. Research has shown that fertilization is ineffective because the tree or shrub does not have any roots yet that can adequately accept the fertilizer. Fertilization becomes effective once the plant has started to become established. Usually this is 3 months to a year after installation. With new installations we recommend some root stimulators and more importantly organic planting mixes. These products will not harm your plants and in most cases these will produce the desired results.

Since root growth is slower in colder climates such as in Colorado, irrigation during the entire year in the first 12-24 months could be required to establish a tree in Colorado. No amount of fertilizer can take the place of proper water throughout the seasons.

When planting new trees and shrubs, soil is often a limiting factor for plant success. Colorado’s soils are typically lacking in the nutrients necessary for a newly installed plant to easily succeed. The most common soil types found in Colorado are clay, sandy, and rocky. When you run into these types of soil you should use a soil amendment.

Soil Amendment Facts:
  • Amendments improve the existing soil but are not used a soil replacement.
  • Soil amendments are mixed into the soil below the surface. Mulch is not a soil amendment because it is placed above the ground.
  • There are specific soil amendments for each type of soil condition.
  • There are specific soils for deciduous and evergreen trees.
  • Soil amendments typically aid in water retention, water permeability, drainage, aeration, and root stimulation.

CreekSide Tree Nursery sells organic soil amendments. We recommend consulting with us on which specific soil to purchase along with your various plant choices. Our staff is trained to get you the right soil for the best plant success possible.


Adequate soil drainage is very important to the overall health of your landscape. If you plant your tree or shrub too deep, you can risk drowning it from a lack of oxygen. Because of this, we always recommend planting your tree or shrub at least a few inches above your natural soil grade. If you feel that your soil might not drain properly regardless, then it is recommended that you test your soils. Dig a 2 foot by 2 foot hole and fill it with water. Then time how long it takes to drain. If you have standing water after 30-45 minutes, that is a big indication of poor drainage. There are many ways to remedy poor drainage, including the addition of soil amendment and drainage pipes. Please consult a professional for tips.

Common statements and questions about purchasing soil amendments are listed below.

Q. I make my own compost. Can I use that?

A. Sure. Just be careful. If you have not used it to plant with before it could be very hot and it could burn you plants. Composting can be simple, but depending on the exact items you’re composting, your compost may not be decomposed enough and you could damage your new investment.

Q. I have some left over soil from my last planting that’s good…isn’t it?

A. In most cases the risk isn’t worth it unless you are very sure. Soil is an important addition to your planting purchase and typically a very small additional cost, which if done properly, the benefits will outweigh the cost. We know it is difficult to keep adding costs to your landscape project…many people skip the soil thing thinking they don’t need it because it is a gimmick. In some instances that could be the case, but in most it is a necessary part of your plants successful life.

Q. I planted before and did nothing to the soil. My plants are fine. So why should I ammend?

A. I’m sure this happened. Soil amendments are not always needed. We have certainly done the same thing. Soils vary greatly and so does plant choice. If you pick the right plants, and have the proper soil already, there is no need to over amend your soil.

Q. When planting, should I dig a huge hole and put good dirt under the plant so its roots will grow easily?

A. No. While we recommend digging a hole as much as three times the width of the root ball, you should not dig it any deeper. If you dig it deeper and fill it with organic matter, the plant will settle over time, causing the plant to tilt, suffocate, and/or drown. The only case to dig deeper is to add a drainage pipe. This is typically not necessary for the majority of plants and should only be done in extenuating circumstances.

Weed Control

Another factor affecting tree and shrub establishment is weed control and the mulch consistency. If weed growth is not controlled around the tree or shrub during the establishment period, it will not allow your newly planted tree or shrub to establish as quickly as it should.

While trees and shrubs are trying to establish, weeds often compete with the limited water that is being supplied. Removing or not allowing weeds and/or grass around the newly planted tree or shrub is necessary for the plants healthy transition and survival. Using mulch will help a great deal in keeping weeds under control around the base of your plants.

Provide weekly irrigation until plants are fully established. At each irrigation, apply 2 to 3 gallons of water per inch trunk diameter (e.g. 4 to 6 gallons for a 2-inch tree) over the root ball only. Once the tree is established after 4 to 8 months you can water twice per month in warm weather in spring, summer, and fall and once a week in winter. Do this for at least the first three to five years.  After this, most trees should be able to survive on natural rainfall with a few supplemental waterings during each season, However keep an eye on your investment.

A newly planted shrub can die in a matter of hours in the hot sun if it does not have proper watering.

These watering schedules typically work for spring, summer, and fall. However, as the summer sun beats down and temperature rise, you may have to increase your watering…especially if you start to see yellow or “crispy” leaves. Because there is much involved in watering a newly planted tree, we’ve listed a few things to keep in mind as you begin to establish this tree in its new home: Yours. You will not always have to hand water your tree or turn on its drip irrigation system. However, keep in mind that the first two years of your plant’s “new life” in your yard will need to be monitored. After two years, and if the tree received proper care, the tree/shrub should have enough roots developed to pull the water it needs from the ground and/or from your sprinkler system’s runoff. Now keep in mind that additional watering is encouraged during the hot and dry period’s throughout your plants life. For an established plant, watering once a month should be a good place to start. Some trees will require more water than others and still others will require significantly less than the recommended amounts above. This will all depend of the variety of tree chosen. When determining a watering schedule, start by looking at your soil. When the tree was planted, was the soil moist or dry? Determine the reason for the moisture or lack there of. If your soil is naturally moist, or your water table is high, you may not have to water your tree as often as your neighbor might. However, the reverse may apply as well. It’s important to note that in Colorado, while we do get some heavy downpours and some wet snows, we do not get enough of either element to correctly water your newly planted tree or shrub.

Just because it rained the week before does not mean you should skip your watering schedule for the current week.

(Ask yourself if you need a drink after just walking out your back door. The same conditions that fatigue us as humans also affect the plants. Remember this when you see your plant just sitting outside day and night without anything to drink.) Water is the key ingredient to a healthy and happy plant. You can use all the root stimulators, fertilizers, and specials composts you can buy, but they are only addons and can never replace the value of water. All roots on transplanted trees are located in the root ball so delivering water on top of the root ball is most efficient.

What does all this mean?

Keep your tree(s) and/or shrub(s) moist. The soil around the tree and the soil located about 18” beneath the root-ball should have the consistency of play-dough. You should be able to ball the soil into your hand without dust being left behind or water squishing out. You do not want dry dirt around your tree, nor do you want mud. It’s the happy medium between the two that should be your goal. On the flip side, it is important to remember that your tree/shrub cannot possibly stay this “moist” forever. Life happens. The soil beneath your tree may dry a bit. This will not kill your plant if it happens occasionally. Ironically, while trees need adequate water to grow, they also need oxygen in order to promote root growth. The roots of your tree will actually begin to spread during these “drier” times, which is why it is impossible for your tree or shrub to stay moist incessantly—the roots are using the water! If trees receive irrigation during establishment and then regularly during the life of the tree, or if you are planting in the plant’s native range and soil type, any tree regardless of drought tolerance can be planted.

Watering your new plants properly is the most important thing you can do.

In addition to exposure irrigation capabilities at the planting site should be considered before selecting trees or shrubs for a planting site. There are many ways to water a tree, however we tend to promote a few ways that produce the best results.

  1. For most situations we tend to water simply, such as with a hose. Or, you can attach a bubbler to the hose and lay it at the base of the tree near the trunk.
  2. We sell a product called a “Tree Gator”. This product can make water super easy. The “Tree Gator” can really help with the winter watering.
  3. If you have the means for a drip irrigation system, by all means use it. Just remember that you still need to pay attention to the tree and make sure that the system is working adequately. We have seen a lot of trees suffer or die simply because their emitter was clogged.

You should also consider the rate at which you water your new plants. Slower is always better. Example: If you take a bucket of water, fill it up, and then dump it out onto the ground, the water will soak in minimally and give you a pretty wide wet spot. Now, if you take that same bucket of water, cut a few small holes in the bottom, fill it up, and then let it slowly drip out over several hours, the water will soak in deeply and the wet spot won’t be quite as wide. If you were to dig down in both instances, you would find that the wet spot from the first bucket would only be wet a couple of inches down in the ground. The second bucket, which dripped the same amount of water but over a long period of time, would be soaked 4-5 times deeper than the first bucket.

We usually reply that the wand is meant for plants with partially or fully established root systems. This is because, most of the time, the wand is used incorrectly and is either obstructive to the roots, or placed in the wrong position. The problem with the wand is usually the depth and the pressure. The wand may sometimes be placed too deep and the pressure too high. This digs holes in the loosened soil under your plants causing them to sink. Also, by applying the water below the roots, the water misses most of the plants “small” root system and basically wastes that water. This can be very inefficient.

Unfortunately, the answer is NO. It can definitely help keep the tree cool in the summer and help add to the water it receives from you during its scheduled watering, but it cannot and must not replace the water you would have given it had the sprinkler system not been there. If you are to rely on the sprinkler system as the sole provider of water for your trees, you must know that you are promoting surface roots. A shallow rooted tree is a bad tree. Instead, deep-root water your tree, by allowing the water to saturate the ground beneath the tree. Again, use a simple hose or drip-irrigation system. Do not rely on your lawn sprinklers to water your trees—trees need directed water to reach the roots.

The answer is YES, you must winter water all newly planted trees…at least for their first winter season and preferably for its first three. If your hose tends to freeze, we recommend you bring your hose into the garage or just coil it up outside after each use during the winter. With that said, your watering schedule will be greatly reduced from its summer and fall months. We recommend as a general rule that you water your tree approximately twice a month, if possible. Your winter watering, which begins as soon as the tree loses its leaves, helps prepare the tree for the long winter and for prepare for “harden off.” Harding off is when the tree begins going dormant in the winter to prepare for spring. Our weather during the winter is mild for the most part and thus, watering is needed. On the days when there are freezes, do not attempt to water your tree. Resume your watering schedule once the weather is not at freezing temperatures.