Celebrate fall with colorful mums

We never know what kind of weather fall will bring. Warm and dry September days keep us outside harvesting delicious fruits and vegetables until first frost — or longer if we’re using plant covers. Late summer’s black-eyed Susans light up the garden, while pink and red hyssops nourish southbound hummingbirds.

Enjoy the waning days of summer. Take it all in while you’re getting started with the early fall garden chores.

It’s ready, set, go for the chrysanthemums. Pick your favorite mum from the overflowing selection at your local garden center or even grocery store. Sure, they’re as common as poinsettias in December, but nothing says “bring on fall colors and cooler weather” like mums. Use them in containers, garden boxes or in the ground.

Chrysanthemums are native to China. Decades of breeding have resulted in the many choices of flower colors and bloom forms. The short list includes single and semidouble mums, which look like daisies; spider, with long, thin, tubular-shaped petals; and pompon, also called button mums, that look like cute little globes.

Flower colors have expanded over the years to include golden yellow, crimson, orange, pink, red, purple, cream and snowy white.

Not all mums are cold hardy to the mostly Zone 5 Front Range. Large-flowered mums, called cutting mums, often included in flower arrangements, are generally not winter hardy so enjoy them in a vase or as indoor potted plants. Hardy mums, also known as garden mums, are perennials. Some varieties are cold hardy to Zone 3 (minus 40 degrees), so easily survive winters throughout Colorado when planted at the best time.

Speaking of timing. The best time to plant mums for deep root establishment is in spring. First, be certain they are hardy garden mums by checking the plant tag or by asking a knowledgeable employee at the garden center where you purchase the plant. They need full sun and fertile, well-draining soil. Keep mums regularly watered through the growing season and while blooming. They will flower in early summer if the blooming buds are not removed (deadheaded) regularly through mid-July. Removing tips with buds helps the plant grow fuller and rounded instead of tall and lanky.

When purchasing mums right now enjoy them two ways — as glorious, short-lived fall annuals that you’ll compost or toss when they’re frozen by hard frost, or give them a go and plant them in the ground and see if they make it. The longer they are given to establish a root system — five or more weeks, ideally — the better their chances for survival. Do not cut back foliage after freezing. Allow the dead foliage to better protect the plant and roots. Wait till spring to cut back the plant.

When purchasing plants now look for flowers that are just showing color or still in bud for a maximized blooming period. Deadhead spent blooms to keep them tidy. They need to be kept moist, but not wet.

Water at the base of the plant to minimize powdery mildew.

Don’t fret if they don’t make it. Make a note to yourself to purchase hardy mums in spring.

• Want to save money by not purchasing so many annual ornamental plants? Grow your own clones this fall. Many outdoor ornamental annuals can be propagated from tip cuttings now (before frost) and grown indoors for winter enjoyment. Plant them outside next spring.

Try coleus, sweet potato vine, lantana, geranium, impatiens and begonia. The key is taking cuttings before a freeze. Take a 4-inch cutting from a healthy branch, remove lower leaves and any flower buds. Dip in rooting hormone (sold at garden centers) and then place in a container of perlite (or very lightweight potting soil). Cover with a clean plastic bag to create a moisture dome until the plant roots — in a few weeks.

See additional tips for propagating at youtube.com/ watch?v=QnSL4H_87dY.

• Plant seeds of quick maturing cool season vegetables — lettuce, spinach, arugula, and other leafy greens, radish, and short-rooted carrots. Tuck in seeds anywhere there is a bit of room or use containers.

• Conifers, or evergreens (fir, spruce, pine, juniper and arborvitae), normally brown and shed older, interior leaves in late summer to fall. It’s no cause for alarm. Read more about it at jeffcogardener.blogspot.com/2017/09/ browning-evergreen-needles-normal-by.html.

• It’s time for some plants to head back inside. Acclimate indoor plants that have been outside all summer by moving them to a full shade location for a few days. This gets them ready for lower light conditions inside the house.

Carefully lift the rootball and check for hitchhiking insects — ants, pill bugs and grasshoppers. Treat with insecticidal soaps or systemic products for scale insects, white fly and spider mites. Remove damaged or leggy growth.

Repot overgrown plants to a slightly larger container. Give them a light fertilizer before moving them indoors. Yellowing or leaf drop is normal until plants get used to being indoors again.

• If you plant to treat your lawn for Japanese beetle larvae (white grubs), next year’s generation of adult beetles, don’t delay. Apply products to the lawn well before frost and cold temperatures set in.

See CSU entomologist Whitney Cranshaw’s handy chart on insecticide and biological control options at extension.colostate.edu/ docs/pubs/insect/05601.pdf.