It is late in the gardening season as I write this, but there is still much to be done this year to make next year’s garden even better.
Grab a camera and take detailed pictures of your garden, as a permanent catalog of your gardening success and failure lessons. Use those pictures in the cold winter months as you dream and plan for next year. While the foliage is yet alive, record your plant varieties and locations. Decide which plants you'll divide and move in the spring--or better yet, donate to the local garden club plant sale).
Late fall can be a good time to build fences to keep out deer and rabbits.
Some Minnesota perennials require winter protection, especially if they are young plants or are marginally hardy in our climate (zone 5 or higher). Cut down dead stems and leaves. Compost all organic material, except diseased plants--dispose those (composting them may not destroy the disease organisms). After the ground freezes (not earlier), mulch plants with 6 inches of clean straw, whole leaves, or pine needles. Remove mulch from the perennials in the spring.
Dig in compost, aged manure, or chopped leaves to your existing garden or to newly prepared gardens. You cannot add too much compost. Run a lawn mower on the driveway to chop up fall’s free bounty of leaves from your lawn. Moonless nights are the best time to obtain bags of leaves from your neighbors without embarrassment.
Fall is a good time to do a soil test; avoid the spring rush (see Soil Testing Laboratory).
You may deadhead your annuals and perennials, or allow them to go to seed. They may reseed naturally at random in our gardens, or you may try gathering and scattering seeds where you want color next spring. Try collecting and drying seeds if you want to wait to plant in spring. Fall is also a great time to plant native forbs and grasses. Many species of wild plants require a cold period (called stratification), before they are able to sprout later in the springtime. Many of our wildflowers rival any of the fancy cultivars found in garden centers, and will do well in our gardens with minimal care. Check Lynn Steiner’s book, Landscaping with Native Plants of Minnesota. Take cuttings from coleus and geraniums to keep indoors over winter. Dig up your tender bulbs such as gladiolus, cannas, and dahlias; store in a cool place with temperatures above freezing (see “Storing Tender Bulbs and Bulblike Structures”.
Put up those bird feeders before the ground freezes. Clean and disinfect feeders before use, and clean them on a regular basis to prevent the spread of disease.
Keep watering trees and shrubs until the ground freezes (usually after Thanksgiving). Adequate fall water lessens the chance of your plants drying and dying during the winter. Enclose small trunks of shrubs and trees with ¼” wire hardware cloth to protect the bark from rodent damage.
Clean, oil, service, and sharpen all your garden equipment so you will be ready to go next year. Put away and lock all chemicals in a clean, dry place out of extreme heat or cold. Dispose old or outdated materials. Now, take a break!
Happy Gardening, Joe Baltrukonis, Ramsey County Master Gardener