The Top 10 Things To Do In Your Garden This Fall

by High Country Gardens

1. Feed the soil

Chilopsis with ornamental Muhly grass

The most important thing we can do for the health of our landscapes, lawns and vegetable gardens is to keep the soil healthy and well fed. I'm dedicated to following organic gardening principles as best I can, so when gardening organically, I feed the soil to feed my plants. And I use a blend of 1/2 Yum Yum Mix (or Yum Yum Mix Winterizer) and 1/2 high quality compost. Spread 1/4 to 1/2" across the top of the soil, either scratched or watered into the surface of the soil and covered with mulch. (Spread the fertilizer mix first, then mulch.)

The soil has a vibrant and complex underground ecology of flora and fauna that will digest this organic food and release it into the soil for plant roots to absorb when they need it. And most importantly, swear off the use of chemical fertilizers and herbicide laden "Weed-n-Feed" fertilizers, as they are harmful to the soil, damaging to the environment and detrimental to the long term health of your plants!

2. Mulch

Mulching is an essential practice in arid climates. In parts of the country where natural precipitation is more than 25 inches annually, mulching is not as important. Long-term use of mulch in moist climates may actually create problems by providing moist habitat for slugs, earwigs and root diseases.

But in dry regions, mulching will:

Protect the soil's moisture from being evaporated by the sun and wind.
Provide a more favorable root growing environment by insulating them from extreme temperatures.
Act as a passive rain harvesting mechanism to help hard, fast rains be absorbed by the soil (especially true when using gravel mulch).

I favor pine needles, small diameter crushed gravel, coarse composted bark, crushed nut shells (if locally available) and clean wheat or barley straw in my vegetable garden. Mulch should be replenished in the fall and again at the start of summer. And don't forget to put down some compost and Yum Yum Mix before you mulch.

3. Plant spring flowering bulbs

A drift of daffodils at the Denver Botanic Garden

To enjoy a beautiful display of tulips, daffodils and other spring blooming bulbs, you need to plant these bulbs now. I like to wait until the leaves are starting to come off the trees and there has been a frost or two to plant my bulbs. So now is an excellent time over much of the country. Keep a bucket of soil mixed with Yum Yum Mix Winterizer (or regular Yum Yum Mix) and high quality compost by your side to put a handful of nutrients into the planting hole for each bulb. Water in thoroughly and apply a one-inch thick layer of mulch to tuck them in for the winter.

And don't forget to take some photos of your bulbs in the spring to create a photographic map to help you remember where to plant more bulbs the following fall.

4. Wait to do clean up until spring

I know many tidy gardeners grit their teeth when I say "wait until spring to cut back your perennials and ornamental grasses." But neatness aside, it's important for your garden's ecology to leave the stems and leaves standing until mid-spring.

Sedum with frost on seedheads

Beneficial insects, butterflies and moths have laid their eggs on the stems and grass blades of your plants and need to be undisturbed until they hatch in spring.
Many perennials and ornamental grasses provide beautiful winter color and texture with their seed heads, leaves and faded flowers.
Leaving the stems on improves the cold hardiness of perennials and improves their ability to overwinter without damage.
In windy climates, standing stems help to capture blowing snow and improve the soil's moisture levels for next year's growing season.

5. Plant perennials

Fall is an ideal time to plant and get a big head start on next year's growing season. - For regions of the country that have mild winters (USDA zone 7 or warmer) and hot summers, this is especially true. In fact, for the Southwestern US, TX. the Southeast, the West Coast and the Pacific NW, now is THE BEST time to plant. And it saves water too.

In colder climates (USDA zone 6 and colder) fall is also excellent for planting.
Perennials with good cold hardiness usually prefer cooler weather to transplant successfully (Oriental Poppies, Columbine, Thyme, Speedwell, Garden Phlox, Catmint, Yarrow and many others).
For zones 3-6, a general rule of thumb is to finish your fall planting 6 to 8 weeks before the soil begins to freeze. In USDA zone 5, the soil begins to harden with frost around the end of November/mid-December, so fall planting needs to be done this week! But in zones 6 and warmer, you can keep going later in the fall.
But not all perennials like fall planting. Those that need a long stretch of hot summer weather to mature their crown and grow deep roots (such as Lavender, Agastache, Salvia greggii (and greggii hybrids) and Desert Willow) should ideally wait until spring.