Just because we’re heading into late fall and winter, it doesn’t mean you need to rip out your garden and store all of your outdoor planters in the garage. Outdoor container gardening is a lot of fun and a great opportunity to be imaginative with your creations!

Create a Welcoming Doorstep

Your front door is the first thing visitors see when they arrive at your home, so why not make a statement with festive containers and planters? Even in the late fall and winter there are many creative ways to make urns, window boxes and containers beautiful with natural plants.

Evergreen tree-toppers are becoming increasingly popular and can be purchased at most area garden centers. Gertens.com provides some easy steps on planting tree tops:

• Pull out all your summer or fall annuals.
• Add extra soil to top off your planters, making sure to leave soil about two inches below the top of the planter.
• Choose greenery – it’s good to buy a variety of sizes and greenery.
• Arrange the tips so taller tips are in the middle and smaller ones are around the edge. You might need to prune them as needed for shape. According to Gertens, you’ll need seven to nine spruce tips for a 12-inch pot.

To make tree-top containers even more beautiful and interesting, embellish them with plants from your garden. Birch and dogwood branches, berries, hydrangeas, pine cones, boxwood bunches, magnolia leaves are just a few plants that add texture and can make your containers beautiful and unique — even under a soft layer of snow. And with a few touch ups, you can enjoy them until spring.

Take a walk through your garden or park and we’re sure you’ll find inspiration from nature!

Be creative with your winter window boxes and containers — with just a few touch-ups, they can create interest until Spring!

The Winter Burn

Every spring we see beautiful bushes turn brown. Why does this happen? It’s called winter burn and is caused when winter sun and wind trigger transpiration (water is lost).  According to the University of Minnesota Extension, damage usually occurs on the south, southwest or windward side of plants.

Winter burn (Kathy Zuzek, UMN Extension)

While all evergreens can be hit with winter burn, yew, arborvitae and hemlocks are particularly susceptible. The UMN Extension has some tips to minimize winter burn:

• Water evergreens until the ground freezes in late fall or early winter.
• Create a barrier around plants that are susceptible to burning, including wrapping them in burlap.
• Apply several inches of mulch around your trees and shrubs for insulation. Snow is a good insulator.
• Pruning weak branch attachments makes trees less susceptible to snow and ice damage.

Wrapping vulnerable trees — like arborvitae — can hep prevent winter burn. (Kathy Zuzek, UMN Extension)

Fall is a great time to think about your perennials.  For several plant varieties, it’s the perfect opportunity to divide them, while other plants can weather the winter season and add to a beautiful landscape!

Don’t Cut Too Early

According to perrenials.com, it’s best to wait until mid or late fall to cut back the tops of plants.  If you cut too early, it can result in a sudden flush of soft growth at a time of year that is risky.  You want to allow perennials to become dormant according to their own natural schedule.

Create Seasonal Interest

Cutting beautiful clumps of ornamental grasses in the fall can also ruin an opportunity to enjoy the contrast of their wheat-colored stems against clean, fresh snow.  But winter interest is entirely subjective, and only you can decide what is attractive or looks tired and messy.  Here are a few tips and ideas:

• Ornamental grasses can remain gorgeous throughout the winter.  Think before cutting them back to the ground before late winter or early spring – some gardeners enjoy wheat-colored grass clumps that contrast with spring-flowering bulbs!
• Did you know that the seed-heads of certain perennials provide food for finches and other birds?  They also look great against a blanket of snow!  Many late-flowering daisy-type perennials are on this list (like Rudbeckia and Purple Coneflower), but others with nice seed-heads and sturdy stems include Achillea, Agastache, Aster, Astilbe, Baptisia, Buddleia, Chelone, Cimicifuga, Eryngium, Eupatorium, taller Sedum, and a few others.
• If you’ve heard that dead-topping perennials can help to trap snow, you might be correct.  For some varieties, snow can be the best insulation against cold temperatures.
• Unlike ornamental grasses, many perennials don’t survive – or sustain – harsh winter months.  We recommend cutting these perennials down in late fall: Alchemilla, Anemone, Campanula, Centaurea, Coreopsis, Delphinium, Dicentra, Euphorbia, Geranium, Hemerocallis, Hosta, Lychnis, Monarda, Nepeta, Oenothera, Phlox (tall types), Trollius, and Veronica.

How Do I Divide Plants?

Grab your shovels and spades!  If possible, water a day or two before dividing to help loosen the plants and bulbs. From there, the process varies depending on what plant you’re working with and whether it’s a root plant or bulb variety.  Check out Gertens.com for specifics on how to divide your perennials.

What Should I Leave Alone?

There are a number of perennials that should be left until spring – they’ll do better when they have a longer regrowth period. Check out the U of M Extension Department for a detailed list.

According to perennials.com, the best time to trim an evergreen is immediately after blooming – if at all! Leave these alone in the fall: Ajuga, Alyssum, Arabis, Armeria, Artemisia ‘Powis Castle’ and ‘Huntingdon’, Aubrieta, Aurinia, Bergenia, Cerastium, Corydalis, Dianthus, Epimedium (trim in late winter, before new buds appear), evergreen Euphorbia, Helianthemum, Helleborus, Heuchera, Iberis, Kniphofia, Lamium, Lavender, Liriope, Origanum, Phlox (creeping types), Primula, Pulmonaria, Sagina, Saxifraga, Sedum (many creeping types), Sempervivum, Teucrium, Thymus, Viola.

Certain woody-stemmed perennials should also be left untouched in the fall and pruned back in the spring, leaving about 6 inches of woody stem for the new buds to appear.  These include: Buddleia, Caryopteris, Erysimum ‘Bowles’ Mauve’, Fuchsia, Hypericum, Lavatera, Perovskia (Russian Sage), Phygelius, Santolina.

Be Careful with Plants with Insect Problems

And, finally, certain perennials with disease or insect problems should not only be cut back in the fall, but be sure to remove and destroy the leaf litter below them, where insects and pathogens may hide. Among these: Alcea (Hollyhocks), Aquilegia (Columbine), Crocosmia, Delphinium, Helenium, Heliopsis, Hemerocallis (Daylily), Iris (Bearded types, leave green leaves alone but remove all dead ones), true Lilies, Monarda, Peonies, Summer Phlox, Tricyrtis, and Veronica (tall types).

Of course, you can always break the rules and see what happens. Just remember that if you move or divide a big, bushy perennial, always cut back the foliage by at least half to prevent serious wilting.  This helps to keep the leaf mass in proportion to the reduced number of roots!