Texas four o’clocks need soil warm enough to germinate, so wait until after the last freeze. The best time to plant four oclock in texas is typically in late March or early April, depending on your specific region. These hardy flowers thrive in the Lone Star State’s warm climate, but timing is everything for a successful bloom.
Four o’clocks are a favorite among Texas gardeners because they’re tough, drought-tolerant, and attract hummingbirds. But if you plant them too early, cold soil can rot the seeds. Too late, and you miss the long growing season. Let’s break down exactly when and how to plant them.
Best Time To Plant Four Oclock In Texas
The ideal window for planting four o’clocks in Texas is after the last frost date, when soil temperatures reach at least 60°F. In most of Texas, this falls between mid-March and mid-April. But Texas is a big state, so your exact timing depends on where you live.
Regional Planting Windows For Texas
- North Texas (Dallas, Fort Worth): Plant from late March to early April. Last frost usually occurs around March 20-25.
- Central Texas (Austin, San Antonio): Plant from mid-March to early April. Last frost typically happens by March 15-20.
- South Texas (Houston, Corpus Christi): Plant from early March to late March. Last frost can come as early as February 20.
- West Texas (El Paso, Lubbock): Plant from mid-April to early May. Last frost may not occur until April 15-20.
- East Texas (Tyler, Longview): Plant from late March to mid-April. Last frost usually by March 25-30.
Check your local extension office for exact frost dates. You can also use a soil thermometer to be sure. Four o’clock seeds need warm soil to germinate, so don’t rush it.
Why Timing Matters So Much
Four o’clocks are warm-season annuals in Texas. They grow best when temperatures stay above 50°F at night. If you plant them in cold soil, the seeds will rot or fail to sprout. Even if they do germinate, a late freeze can kill young seedlings.
On the flip side, planting too late in summer means less time for the plants to establish before the intense Texas heat. They’ll still grow, but you might get fewer flowers. The sweet spot is when soil is warm but air temperatures haven’t hit 95°F yet.
How To Prepare Your Soil For Four O’Clocks
Good soil preparation makes a huge difference. Four o’clocks aren’t picky, but they do best in well-draining soil. Texas clay soil can be a problem if it stays wet too long.
Steps To Prepare Your Planting Area
- Choose a spot with full sun to partial shade. Four o’clocks bloom best with at least 6 hours of direct sunlight.
- Loosen the soil to a depth of 8-10 inches. Use a garden fork or tiller.
- Mix in 2-3 inches of compost or aged manure. This improves drainage and adds nutrients.
- Rake the area smooth and remove any rocks or debris.
- Water the soil lightly a day before planting to settle it.
If you have heavy clay soil, consider planting in raised beds or containers. Four o’clocks can handle some drought, but they don’t like wet feet.
Soil Temperature Check
Before you plant, check the soil temperature. Insert a soil thermometer 2-3 inches deep. Wait until it reads at least 60°F consistently for three days in a row. If you don’t have a thermometer, watch for signs like dandelions blooming or oak trees leafing out—these are natural indicators that soil is warming up.
How To Plant Four O’clock Seeds
Four o’clock seeds are large and easy to handle. They have a hard outer coat, so they benefit from a little prep work. Here’s how to plant them correctly.
Seed Preparation
- Soak the seeds in warm water for 12-24 hours before planting. This softens the seed coat and speeds up germination.
- Alternatively, nick the seed coat with a nail file or sandpaper. This is called scarification.
- Do not soak for more than 24 hours, or the seeds may rot.
Planting Steps
- Dig holes 1/2 to 1 inch deep. Space holes 12-18 inches apart.
- Drop 2-3 seeds in each hole. This ensures you get at least one plant per spot.
- Cover the seeds with soil and pat down gently.
- Water the area lightly. Keep the soil moist but not soggy until seeds sprout.
- Mark the planting area so you don’t forget where you planted.
Seeds usually germinate in 7-14 days if soil is warm enough. If it’s cooler, it may take up to 3 weeks. Be patient and keep the soil moist.
Caring For Four O’Clocks After Planting
Once your four o’clocks are up, they’re pretty low-maintenance. But a little care goes a long way in Texas heat.
Watering Tips
- Water deeply once a week during dry spells. Four o’clocks are drought-tolerant once established.
- In extreme heat (above 95°F), water twice a week.
- Water at the base of the plant to avoid wetting the leaves, which can cause fungal issues.
- Mulch around the plants with 2-3 inches of organic mulch to retain moisture and keep roots cool.
Fertilizing
Four o’clocks don’t need much fertilizer. Too much nitrogen will give you lots of leaves but fewer flowers. Use a balanced, slow-release fertilizer like 10-10-10 once at planting time. That’s usually enough for the whole season.
Pruning And Deadheading
Four o’clocks bloom from late spring until the first frost. Deadheading (removing spent flowers) encourages more blooms. But it’s not strictly necessary. If you want them to self-seed for next year, leave some flowers to go to seed.
You can also cut back leggy plants by about one-third in midsummer. This promotes bushier growth and more flowers.
Common Problems With Four O’Clocks In Texas
Four o’clocks are generally pest-free, but a few issues can pop up. Here’s what to watch for.
Pests
- Aphids: These tiny insects suck sap from new growth. Spray them off with a strong stream of water or use insecticidal soap.
- Spider mites: In hot, dry weather, spider mites can attack. Keep plants well-watered and mist the leaves occasionally.
- Japanese beetles: They may munch on leaves. Hand-pick them or use neem oil.
Diseases
- Powdery mildew: This white fungus appears in humid conditions. Improve air circulation by spacing plants properly. Avoid overhead watering.
- Root rot: Caused by overwatering or poor drainage. Plant in well-draining soil and don’t water too often.
Other Issues
- Poor germination: Usually due to cold soil or old seeds. Always use fresh seeds and wait for warm soil.
- Leggy growth: Too much shade or too much nitrogen. Move plants to a sunnier spot or reduce fertilizer.
- No flowers: Often caused by too much shade or over-fertilizing. Four o’clocks need sun to bloom.
Growing Four O’Clocks In Containers
If you have limited space or poor soil, containers are a great option. Four o’clocks grow well in pots, and you can move them around to catch the sun.
Container Tips
- Use a pot at least 12 inches wide and deep. Larger is better for root growth.
- Make sure the pot has drainage holes. Four o’clocks don’t like standing water.
- Use a high-quality potting mix, not garden soil. Garden soil compacts in containers.
- Water more frequently than in-ground plants. Containers dry out faster in Texas heat.
- Fertilize with a liquid fertilizer every 4-6 weeks during the growing season.
Container-grown four o’clocks may need to be watered daily in summer. Check the soil moisture by sticking your finger an inch deep. If it’s dry, water.
Harvesting And Saving Four O’clock Seeds
Four o’clocks produce lots of seeds, and they’re easy to save for next year. This is a great way to save money and share with friends.
How To Collect Seeds
- Wait until the flowers fade and the seed pods turn brown and dry. This usually happens in late summer or fall.
- Pick the pods off the plant. They look like small, wrinkled berries.
- Crush the pods to release the seeds. The seeds are large, black, and hard.
- Spread the seeds on a paper towel and let them dry for a week in a cool, dry place.
- Store the seeds in a paper envelope or glass jar. Label with the date and variety.
- Keep them in a cool, dark place until next spring. They stay viable for 2-3 years.
Four o’clocks also self-seed readily. If you don’t collect the seeds, they’ll drop and grow on their own next year. Just be aware that they can spread, so plant them where you don’t mind them coming back.
Companion Planting With Four O’Clocks
Four o’clocks are great companion plants. They attract pollinators and can help deter pests. Here are some good neighbors.
Good Companions
- Marigolds: They repel nematodes and add color.
- Zinnias: Attract butterflies and bees.
- Cosmos: Easy to grow and complement four o’clocks.
- Basil: Repels mosquitoes and other pests.
- Lantana: Another Texas favorite that thrives in heat.
Plants To Avoid
- Tomatoes: Four o’clocks can attract the same pests, like aphids.
- Potatoes: They may compete for nutrients and space.
- Other heavy feeders: Four o’clocks don’t need much fertilizer, so avoid planting them with plants that require lots of feeding.
Four O’Clock Varieties For Texas
There are several varieties of four o’clocks, and some do better in Texas than others. Here are a few popular choices.
- Mirabilis jalapa: The common four o’clock. Comes in red, pink, yellow, white, and striped. Very heat-tolerant.
- Mirabilis multiflora: Also called Colorado four o’clock. Native to the Southwest and very drought-tolerant.
- Mirabilis longiflora: Has long, tubular white flowers that open at night. Fragrant and attracts moths.
- ‘Jingles’ mix: A dwarf variety that stays compact. Good for containers.
- ‘Alba’ white: Pure white flowers that glow in the evening.
All of these varieties grow well in Texas. Choose based on your space and color preferences.
Frequently Asked Questions
When is the best time to plant four o’clock seeds in Texas?
The best time is after the last frost, when soil temperatures reach 60°F. For most of Texas, that’s late March to mid-April. Check your local frost dates for precision.
Can I plant four o’clocks in the fall in Texas?
Yes, you can plant them in early fall for a late bloom, but they may not have time to fully establish before the first frost. Spring planting is more reliable for a full season of flowers.
Do four o’clocks come back every year in Texas?
They are annuals in most of Texas, but they self-seed readily. If you let the seeds drop, new plants will appear next spring. In warmer parts of South Texas, they may act as short-lived perennials.
How deep should I plant four o’clock seeds?
Plant seeds 1/2 to 1 inch deep. Any deeper and they may not germinate. Cover lightly with soil and water gently.
Can I start four o’clock seeds indoors in Texas?
Yes, you can start them indoors 4-6 weeks before the last frost. Use seed-starting mix and keep the soil warm (70-75°F). Transplant outdoors after the danger of frost has passed.
Final Tips For Success
Four o’clocks are one of the easiest flowers to grow in Texas. They laugh at the heat and bloom when other plants are wilting. Just remember these key points:
- Wait for warm soil. Don’t rush it.
- Soak seeds before planting for faster germination.
- Space plants 12-18 inches apart for good air flow.
- Water deeply but infrequently once established.
- Enjoy the evening show—four o’clocks open in late afternoon and bloom all night.
With the right timing, you’ll have a beautiful display of four o’clocks from late spring until the first frost. They’re a rewarding plant for any Texas garden, whether you’re a beginner or a seasoned pro. Happy planting.