Although it hasn't started to cool off considerably this year, winter tends to sneak up on us with the hustle and bustle of the end of the year.  If you don't plan ahead, your garden will get frosted before you know it.
Landscaping-Tips-Plano-how-to-prepare-a-garden-for-winter
The Dallas - Fort Worth area is in USDA hardiness zones 7b and 8a, which means the average minimum temperature is 5 to 15 degrees Fahrenheit. Growing conditions are warmer than in northern gardens, but plants grown in these zones can still be sensitive to decreasing temperatures and benefit from winter protection.
One of the most important things you can do for your garden, whether you are getting a flower garden ready for winter or planting a winter vegetable garden, is mulching. Mulch keeps plant roots warmer in the winter, holds moisture in the soil, and reduces weed growth. Shredded leaves, wood chips, bark, and straw are organic mulches. They have the additional benefit of amending the soil as they break down. Inorganic mulches, such as rocks and synthetic fabrics, will reduce moisture loss, moderate soil temperature, and reduce weeds, but they don't contribute to the overall health of the garden soil.

Flower Gardens

There are a few winter prep tasks specific to flower gardens. If you start on your pre-winter task list early enough, fall is a great time for transplanting and putting in new plants. The plants are less likely to be shocked by transplant when the weather is cool and the soil does not dry out as fast. Fall, even late fall, is also the best time to plant spring bulbs like tulips, daffodils, and hyacinth. The Southern Bulb Co. sells these bulbs, and also provides a list of suggested bulbs to plant in the spring and fall. Before mulching, clean out dead leaves and flower stalks on perennials and grasses that have started to go dormant. Pull out any annuals that have stopped blooming. All of this can go on the compost pile and be used as fertilizer or mulch after it starts breaking down. While you're cleaning up the flower beds, don't do much pruning. It stimulates growth, and is better as a spring task.

Vegetable Gardens

Begin by pulling plants that are no longer producing. Winter is a good time to have the soil pH tested and amend accordingly. Compost will balance the pH of soil whether it is acidic or alkaline, and is the best option for alkaline soils. If your soil is acidic and compost is not enough, you can add lime. Late in the year is a good time to add lime, because it should be applied when no plants are present. Winter in the Forth Worth area need not mean the end of the growing season. This is an ideal time to grow cool-season crops that would wither in the hot summer. Lettuce, kale, carrots, broccoli, cauliflower, cabbage, beets, onions, radishes, and peas are some of  the plants that thrive in cool growing conditions. Two weeks before planting a winter garden, amend, fertilize, and till the soil. For more information about cool-season gardening in zones 7-9, check out this website.

Other Winterizing Tips

  • Keep an eye out for garden pests. If you're growing a winter garden, cabbage worms can be an issue even as it gets cooler.
  • Clean garden tools to prepare for next spring.
  • Herbs that would die or go dormant in the winter can be potted up and brought inside. Place on a sunny windowsill and water regularly to enjoy fresh herbs through the winter.
For Texas gardeners, winter does not mean the end of gardening. Gardeners can keep busy amending the soil in garden plots, mulching existing flower beds, and growing winter vegetables. Come spring, the work you've done to prepare your soil and plants for winter will make planting easier and help your gardens grow well.