Texas consists of United States Department of Agriculture (USDA) plant hardiness zones 6a to 9b with low winter temperatures that average anywhere between minus five degrees and plus 30 degrees F. Select bulbs hardy to your zone and plant them in the fall to grow as perennials. However, if your climate is hotter than the bulbs require, plant them in mid- to late-winter to grow as annuals, or if desired, dig them up in the fall, then chill them in the refrigerator or another cold area to give them the required chilling period so you can plant them again in the next winter.
Choose a location to plant your bulbs. Most bulbs, such as tulips and crocuses, prefer full sun (at least six hours of sunlight), but a few, such as bluebells and callas, prefer partial shade (three to six hours of sunlight). If your bulbs require full sunlight and you live in an area of Texas that is located in USDA plant hardiness zones 8 and 9, choose a planting site that has some shade in the early to mid afternoon when the sun is the strongest, but still receives at least six hours of sunlight a day. This will help prevent the bulbous flowers from wilting and drying out.
Amend the soil by turning over the top foot of soil with a garden rake, hoe or tiller, then integrate about 6 inches of compost or peat moss into the soil to improve water drainage and the quality of the soil. This will also create a slightly raised planting bed to help with water drainage. However, if your soil contains a lot of clay, as it does in many parts of Texas, such as near Dallas, integrate 3 inches of compost and 3 inches of coarse sand, gravel or aerated gravel (e.g., expanded shale) into your soil instead of only compost or peat moss.
Dig holes two to three times as deep as the bulbs are wide. For example, if the bulbs are 2 inches wide, plant them 4 to 6 inches deep. This is a general rule that applies to most bulbs; however, always follow the directions that come with your bulbs.
Space bulbs at varying intervals, depending on the bulbs. Bulbous plants that grow wide, such as daffodils, need much more space than small bulbous plants like crocuses. If the bulbs are winter hardy in your area of Texas, consider planting the bulbs about 2 to 3 inches further apart so you do not have to dig them up and divide them as often as you would if they were planted closer together. Remember, bulbs self propagate and will become overcrowded in time.
Sprinkle a bulb fertilizer, bulb booster or bone meal at the bottom of each hole. Follow the dosing instructions, but usually less than a tsp. for each hole will suffice. In addition, to prevent contact with the bulbs, cover the fertilizer, bulb booster or bone meal with about ¼ inch of soil.
Plant the bulbs with the tips facing up toward the top of the ground. Backfill the soil and tamp it down lightly. Water the bulbs well with about an inch or two of water.
Add about 3 inches of mulch, such as wood chips or bark. Much of Texas experiences scorching summers and sometimes droughts, and mulch will help the soil maintain more even soil temperatures and also help it retain and conserve water.