Ask the Arborist: Tree Planting in Boulder

A homeower planting a new tree with an added mulch ring to promote health and growth.

Q: Can I plant new trees in late fall to early winter, because this is a great time to find them on sale?

A: It’s not advisable, but can be done. Since your irrigation is turned off and we never know how much snow we will get here in the foothills, it will be difficult for your new tree to establish. Frozen ground, or heavy snows can be hard on a new tree.

We suggest planting in Spring when you have turned your irrigation on, or early fall when the temps cool, but you still have access to water. Fertilization is also recommended for new trees and the best time to fertilize is in spring or in early fall. You want the tree to take up as much nutrients as possible and this is difficult in frozen or dry ground.

If you do plant late we advise having a plan in place for deep root watering or winter watering. It is also advisable to provide your new tree with a mulch ring to keep in soil moisture.

Please see our previous blog on the benefits of native mulch.

If you are planting late, watch the forecast and try to choose a time when we have a few sunny warm days in a row, make sure the soil is prepared and nutrients are readily available to help promote your trees vitality through the winter months.


Q: Why did my neighbor have to plant that huge Oak tree right by our property line, it’s a disaster waiting to happen?

A: Well, we don’t know your neighbor, but we can say that instant gratification happens a lot in landscape and arborscape planning.

People want their property to look and feel full, and complete right away. Often times to get that feeling trees and shrubs that will be too large for the space in 5 years, but fit right now, are chosen.

It is advised before you plant to meet with an arborist to discuss tree placement. Different trees and shrubs require different things. Some may need full light, others partial shade. Some are better west facing, others north.

Being educated about the plants and trees you place on your property is key. Things to investigate are sun and shade requirement, water requirement, specific soil or nutrients, and of course, what the mature root system and mature tree size will be. Also, we advise clients to look up and around, not just on the ground.

When your new tree matures will it create a highway of animals to your roof and attic, will it hang onto your neighbor’s property or over their roof, or will your tree grow into the power lines? When you buy a house a problem like this may already exists, and proper tree branch pruning can make a situation like this not so bad, but why create a new situation with poor tree placement?

These questions were submitted to us on our website by real people. Have a question for an Arborist? Contact us today!

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At Blue River Forestry & Tree Care, we love trees and are committed to the health and care of yours! We offer all aspects of arboriculture, including tree trimming and pruning, tree removal, cabling and bracing, tree planting, Emerald Ash Borer consultation and treatment, plant health care services, and forestry services.

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