November Tasks in the Ornamental Garden
There’s a surprisingly long list of tasks for the month of November.
You can keep planting new deciduous trees and shrubs this month, at least until the ground freezes. Planting them during cool autumn weather allows them to become established before next summer’s hot weather arrives. As long as the soil temperature is above 40°F, roots will continue to grow, and that root growth enables the tree to thrive and survive. Frankly, with the extreme heat and drought we’ve been experiencing in recent years, fall has become my main planting season. Please note that fall is not the ideal time for planting broadleaf evergreens.
Before you bring a tree or shrub home from the nursery, do some advance thinking and planning, and here’s a good place to start: Planting a New Tree, The Garden Shed, Nov 2015. In order to choose the right tree for your site, consult Right Tree/Right Place List/C’ville Tree Stewards If you wish to plant on very compacted soil, you’ll need to amend a large area (not just the planting hole), as directed in Univ.of Maryland Ext. Planting Process/Shrubs & Trees. There you’ll also learn about the benefits and methods for creating “tree islands” for multiple trees.
Before you start digging a hole, consult some expert tree-planting instructions, such as those at Univ.of Maryland/Planting Process – Trees & Shrubs and Tree Planting Guide, C’ville Tree Stewards, The Charlottesville Tree Stewards recommend turning your tree into a “bare root” tree before planting, and they have produced a video to show you how. Tree Planting Video/C’ville Tree Stewards If it’s a balled and burlapped plant, you can read more at Univ.of Ky. Planting Balled and Burlapped Trees and Shrubs in your Landscape,
Or perhaps you’d like to watch a tree-planting video? In addition to the Tree Stewards video mentioned above, you’ll find tree-planting videos at Planting a Container Grown Tree Video Univ.Md.Ext. or How to Plant a Tree in Your Landscape Univ.N.H.Ext..
As these publications and videos explain, it’s very important to dig a hole that is wider than the root ball — most experts prescribe a hole that is at least two to five times wider than the diameter of the root ball but no deeper than the height of the root ball. Remove any wires, ropes, and non-biodegradable material from the root ball before back filling the hole, and if you’ve got a containerized plant, you’ll need to deal with any circling roots. The received wisdom on circling roots has involved cutting them, but some authorities now suggest simply breaking a few and loosening them from the soil of the root ball, as demonstrated in the video mentioned above, Video: How to Plant a Container Grown Tree Do NOT add any soil amendments such as compost or peat moss to the planting hole because they encourage the roots to stay in the planting hole instead of growing outward. After you finish backfilling, apply about 1-2 inches of mulch over the site but don’t let the mulch touch the trunk of the plant. Leave a 2” to 3” gap between the mulch and the trunk or stem. Water the plant well but not to the point that the soil becomes soggy. You’ll need to keep watering regularly for a year to get your tree established.
Finish planting spring bulbs. VCE Publication 426-201, “Flowering Bulbs: Culture and Maintenance” recommends a planting depth of 2½ to 3 times the diameter of the bulb. In other words, if your bulb is 2” in diameter, plant it 5” to 6” deep (that’s from the top of the soil to the bottom of the bulb). While some bulbs can tolerate some shade, most of them do best in a sunny site that drains well. Read all about it at Va.Coop.Ext. Flowering Bulbs.
Many trees and shrubs can still be transplanted this month. Smaller trees and shrubs can be transplanted when dormant. But unless you did some advance root-pruning six months ago, don’t try transplanting larger trees and shrubs now. Tree and shrub roots normally grow well beyond the soil volume that can be moved; in established trees, the roots extend 50% beyond the drip line. To keep most of the roots within a small area, these roots need to be pruned at least six months in advance of transplanting. Ideally, root pruning is done in stages about 1-to-2 years before the plant is transplanted. Plants to be moved in the fall (October or November) should be root pruned in March, and those to be moved in spring (March) should be root pruned in October. Root prune only after leaves have fallen from deciduous plants in fall or before bud break in the spring. If not root pruned, the plant may die from transplant shock because of root loss.
If you intend to transplant a good-sized tree or shrub, you can certainly do your initial root pruning now. Begin root pruning by marking a circle the size of the desired root ball around the tree or shrub. Then dig a trench just outside the circle. For detailed instructions on both root pruning and transplanting, I strongly recommend the detailed instructions at Clemson’s Home & Garden Information Center, HGIC/Clemson.edu and at Univ.Md.Ext./Trees & Shrubs Planting Process.
There’s still time to remove woody invasives using methods that apply a small amount of herbicide to a cut in the stem or trunk — the “hack and squirt” method and the “cut stump” method, for example. Late fall is actually a good time for these methods, according to the Blue Ridge PRISM, because
“when actively growing, plants send nutrients and water upward, so an herbicide may not be moved down into the root system. From late summer into late fall, movement is downward into the roots for winter storage, so herbicide applied at that time does an effective job.”
blueridgeprism.org/How-to-Control-Invasive-Plants-Effectively-and-Safely-with-Herbicides. For more about these methods and when they’re effective, take a look at Southeast Exotic Pest Plant Council/Application Methods for Recommended Herbicide Treatments.
If you’d like to enjoy paperwhite narcissus and amaryllis over the holidays — or give them as holiday gifts — now’s the time to get started. Plant paperwhite bulbs, pointy side up, in soil or in water. In just a few days, roots will sprout, and in about 4 to 5 weeks, blooms will emerge. Plant around Thanksgiving for bloom at the holidays. Amaryllis is another bulb that can be started in November for holiday season bloom. On average, amaryllis will bloom about 6 to 8 weeks after planting. For detailed planting and care information, read The Garden Shed/Amaryllis .
It’s not too late to apply fertilizer to your lawn, though it should be a nitrogen-only fertilizer. For cool-season grasses, the preferred time for applying N fertilizer is August through October. The second best time is late fall, mid-October to late November, when cool temperatures have reduced top growth, but root growth is still active. Low rates of N fertilizer (40 to 50 lbs./acre) will “set-up the plant” for winter and encourage healthy early-spring growth. Not only does enhanced root growth aid in the uptake of water and nutrients, carbohydrate buildup in the stem bases promotes winter survival and spring regrowth. Never apply lawn fertilizer to frozen soils. For warm-season grasses, the preferred period for applying N is mid-April through mid-August. For overseeded lawns only, a secondary period for applying a fall nitrogen application is mid-October to mid-November.
For recommendations on appropriate fertilization schedules and application rates, see the VCE publications, “Maintenance Calendar for Cool-Season Turfgrass Lawns in Virginia,” at Va.Coop.Ext. Pub. No. 430-523and “Maintenance Calendar for Warm-Season Lawns in Virginia,” Va.Coop.Ext. Pub.No.430-522.
Were you thinking about fertilizing trees and shrubs? Think again. Mature trees and shrubs generally don’t need fertilizing, and in any event, it’s generally called for only if you’re seeing symptoms of under-sized growth such as pale or small leaves, twig die-back, and the like. You’ll need a soil test to determine if nutrients are needed. Also, you’ll need to wait until the tree or shrub is dormant to apply fertilizer, which should be applied over as much of the root zone as possible, not concentrated around the stem or trunk. By the way, if you’re fertilizing the lawn, tree and shrub roots that extend into the turf area absorb some of the fertilizer, and are therefore indirectly fertilized. For further information, see the VCE publication, Va.Coop.Ext. Fertilizing Landscape Trees & Shrubs.
You may want to review our previous tasks and tips articles, some of which cover additional tasks or provide additional details about November tasks in the ornamental garden.
Tasks & Tips Nov. 2015 (general yard tasks, tool maintenance)
Tasks & Tips Nov. 2016 (garden clean-up, mulching, winter care of tropicals)
Tasks & Tips Nov. 2017 (preparing the garden for winter) (houseplant care)
Tasks & Tips Nov. 2018 (winter prep for container plants; protecting trees & shrubs from mammals)
Featured photo: by Piers Nye