A fall garden in New Mexico featuring Chrysothamnus (Rabbitbrush), Helianthus maximiliana (Maximilian's Sunflower), Perovskia (Russian Sage), and various ornamental grassesA fall garden in New Mexico featuring Chrysothamnus (Rabbitbrush), Helianthus maximiliana (Maximilian's Sunflower), Perovskia (Russian Sage), and various ornamental grasses

The Advantages Of Fall Planting

While fall is a great time to transplant perennials, shrubs, and trees across the country – in the Southwestern US, where winters are mild and summers are extremely hot, fall is the best time to plant! 

The changing season means that air temperatures are cooling, while soil is still warm from the summer sun. These conditions are ideal for establishing new transplants. Don't miss out on the benefits of planting this season to enhance your garden, give your new plants the best chance of success, and help save water, too.

Fall planted perennialFall planted perennial
In Fall, cooling air temperatures and warm soil temperatures are ideal for establishing new transplants.
Fall-planted perennial in winterFall-planted perennial in winter
In late Fall and Winter, perennial root growth continues, while the plant enters dormancy and require less water.
Spring-planted perennial vs. fall-planted perennialSpring-planted perennial vs. fall-planted perennial
In early Spring, fall-planted perennials are ready for vigorous growth and earlier flowering.
Spring-planted perennial vs. fall-planted perennial in summer.Spring-planted perennial vs. fall-planted perennial in summer.
By Summer, established fall-planted perennials result in larger growth and more resilient plants in tough weather.

Why Fall Planting Benefits Plants, Season By Season

Fall planting means strong roots. 80% of a plant's root growth occurs in the late summer and fall months. While you won't see as much stem and leaf growth in the fall, the plants are busy growing new roots. With the arrival of spring, fall-planted perennials are ready to burst forth with vigorous new growth and a profusion of flowers.

  • In Fall: cooling air temperatures and still-warm soil temperatures are ideal for establishing new transplants.
  • In Late Fall and Winter: root growth will continue as long as the soil is not frozen. This continued root growth increases the number of nutrients stored in the plant over the winter. Perennials usually enter dormancy around late fall or summer, and resume active growth in spring - but different perennial species will have different seasonal timing. 
  • In Early Spring: fall-planted perennials will have a more established root system, and they'll be ready for vigorous growth and earlier flowering. These established plants are not held back by transplant shock, as compared to new spring-planted perennials.
  • In Late Spring and Summer: your fall-planted perennials will display larger top growth, more abundant flowering, and more resilient plants. As well-established plants with strong roots, they will be more drought-tolerant, and better able to handle the harsh, drying winds of spring and the withering heat of summer.

Why Fall Planting Is Ideal For Waterwise Gardens

Fall planting is also beneficial for gardens in dry climates or – any garden that is experiencing drought conditions.

As plants begin to go dormant in the fall, and their energy shifts from top growth to root growth, they use much less water. Plus, soil is cooler in the fall, and the weather tends to be less windy than spring. As a result, plants and soil are also less likely to dry out from heat and evaporation. Less frequent watering not only helps to conserve resources and makes caring for new transplants easier, too.

In spring, young plants are well-established with strong roots, so they will be more drought-tolerant by the time spring and summer weather arrives.

Fall Planting & Watering Tips

  • For 4-6 weeks after planting in fall, the perennial will continue to send new roots out into the soil. Once a plant is established, watering frequency can be reduced. Water regularly through the fall months, decreasing frequency as the daytime temperatures cool in late October and November. 
  • In winter, soak plants once every 2-3 weeks if there is no rain, until the ground is frozen solid.
  • In zone 5 and colder regions, the soil begins to freeze up in early to mid-November and stays frozen through January. By early to mid-February, when daytime temperatures begin to rise consistently above 45-50°F and the soil begins to thaw, you can begin soaking plants every 2-3 weeks.
  • For best results, we recommend using Superthrive root stimulator and Plant Success Soluble Mycorrhizal Root Inoculant at the time of planting to encourage healthy root growth.
  • Mulching is also essential to successful fall planting. It keeps the plants from drying out in the dry fall and winter weather, and will keep the soil frozen over the spring months to prevent frost heaving of the roots.
Cooling air temperatures and warm soil temperatures are ideal for establishing new transplants.
Root growth continues slowly through the late fall and winter, as long as the soil is not frozen.
Compared to spring-planted perennials, plants installed in the fall grow more rapidly in the spring.
With a more established root system, fall-planted perennials are much better able to handle the harsh, drying winds of spring and the withering heat of summer.

Why Fall Is An Ideal Time to Plant

September and October are excellent times to transplant perennials, shrubs, and trees across the country – but in the Southwestern US, where winters are mild and the summers are extremely hot, fall is the best time to plant! 

The changing season means that air temperatures are cooling, while soil is still warm from the summer sun. These conditions are ideal for establishing new transplants. Although you won't see a lot of stem and leaf growth in the fall, the plants are busy growing new roots. With the arrival of spring, the fall-planted garden is ready to burst forth with vigorous new growth and a profusion of flowers.

 

Fall Planting: Growing Strong Roots

80% of a plant's root growth occurs in the late summer and fall months. Root growth continues slowly through the late fall and winter, as long as the soil is not frozen. Better root growth increases the number of nutrients stored in the plant over the winter.

Compared to spring-planted perennials, which suffer a period of transplant shock and take time to establish their roots and begin to grow, plants installed in the fall grow rapidly in the spring—with more vigorous top growth and flowering because their roots were established over the fall and winter.

With a more established root system, fall-planted trees, shrubs, and perennials are much better able to handle the harsh, drying winds of spring and the withering heat of summer.

 

Fall Planting For Waterwise Gardening

Fall planting is better from a water-use perspective:

  • As plants begin to go dormant in the fall, they use less water.
  • The soil is cooler in the fall, so it stores moisture better.
  • You'll need less water, and watering chores are much easier, because you have to water less frequently.
  • Fall is less windy than spring. Wind dries out the soil quicker and dehydrates plants.

For best results, be sure to use Superthrive root stimulator is used at the time of planting to encourage healthy roots, and apply the mixture several times after planting. Also, be sure to inoculate the roots with the water soluble Plant Success mycorrhizal inoculants—root inoculation only needs to be done once at planting time.

Mulching is also essential to successful fall planting. It keeps the plants from drying out in the dry fall and winter weather, and will keep the soil frozen over the spring months to prevent frost heaving of the roots.

 

Fall Watering For Waterwise Gardening

Water is crucial during the fall and winter. Water regularly through the fall months, decreasing frequency as the daytime temperatures cool in late October and November. From 4-6 weeks after planting, the plant should have pushed new roots out into the planting hole.

Once a plant is established, watering frequency can be reduced. When the soil begins to freeze, soak it once every 2-3 weeks through the winter months, except when it is very cold and the ground is frozen solid. In zone 5 and colder regions, the soil begins to freeze up in early to mid-November and stays frozen through January. By early to mid-February the day temperatures will begin to rise above 45-50° F providing an opportunity to water.

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