tomato sprouts

When to Plant Tomatoes in Zone 8

Growing tomatoes in zone 8 can present some unique challenges, but none of them are insurmountable. Mild winters and hot summers make this zone well-suited to growing tomatoes. Some challenges include early blight, temperature stress, and pests. Many companion plants can help protect your tomato plant from stressful elements.

USDA Hardiness Zone 8 Climate

USDA hardiness zone 8 covers a range of areas in the United States with an average minimum temperature range of 10 to 20°F (-12 to -7°C). The climate in this zone is typically characterized by mild winters and hot summers, with late freezes in the spring and early freezes in the fall.

One of the challenges associated with growing tomatoes in zone 8 is the risk of early blight and other tomato diseases that thrive in warm, humid conditions. These diseases can weaken the plants and reduce yields, so it’s important to choose disease-resistant tomato varieties and to provide good air circulation around tomato plants. Not too much wind though as this can negatively affect your harvests.

High temperatures, drought, or extreme humidity are common issues with zone 8 summers. Overheating or underwatering can ruin a harvest. The temperature stress can also affect the tomato’s flavor. It’s important to provide consistent moisture to tomato plants during these periods, either through regular irrigation or by using mulch to retain soil moisture.

Overall, growing tomatoes in USDA hardiness zone 8 can be successful with proper care and attention. Choosing appropriate tomato varieties, providing good air circulation, consistent moisture, and protecting against high temperatures can all help ensure a bountiful tomato harvest in this region.

When to start tomatoes indoors in zone 8

If you want to get an early start on cultivating tomatoes, begin growing the seeds indoors 4-6 weeks before the final spring frost in your area, regardless of the tomato variety you’re growing. In zone 8, you’ll want to start your tomato plants indoors around February 14th.

You may want to get them going even earlier than that and plant them in a large pot ahead of planting them outdoors, just to give them even more of a head start. To start tomato seeds indoors:

  1. Select a planting container. Choose a container that is at least 6-8 inches deep, with holes in the bottom for drainage.
  2. Fill with a seed starter potting soil.
  3. Plant 2-3 tomato seeds ⅛ inch deep in the soil and cover.
  4. Water the soil until it is moist but not soggy.
  5. Place the container in a warm, sunny spot indoors and keep the soil moist.
  6. When the seedlings reach 2-3 inches tall, thin them out so there is only one seedling per container.

Tomato varieties that do well in zone 8

Growing early-harvest tomatoes is essential in zone 8, due to the shortened growing season. Some varieties of tomatoes are ready to harvest in under 60 days, which is ideal in the short growing season of zone 8. I recommend one of the following varieties: 

  1. ‘Aunt Gertie’s Gold’ Tomato – 75-80 Days to Harvest
  2. ‘Heidi’ Tomato – 90 Days to Harvest
  3. ‘Opalka’ Tomato – 90 Days to Harvest
  4. ‘Martino’s Roma’ Tomato – 70-80 Days to Harvest
  5. ‘Cherokee Purple’ Tomato – 80 Days to Harvest
  6. ‘Brandywine’ Tomato – 80-100 Days to Harvest
  7. ‘Tidwell German’ Tomato – 80 Days to Harvest
  8. ‘Celebrity’ Tomato – 70 Days to Harvest
  9. ‘Chapman’ Tomato – 80 Days to Harvest
  10. ‘Gardener’s Delight’ Tomato – 65 Days to Harvests

Hardening off your tomatoes

Hardening off tomatoes that you’ve started indoors before planting outdoors is important to ensure they can thrive in the outdoor environment. When tomatoes are started indoors, they become accustomed to the warm and more stable environment. When planted outdoors, they are exposed to more extreme temperatures, wind, and sun. Hardening off tomatoes helps them slowly adjust to their new environment by exposing them to these elements for an extended period.

The process of hardening off tomatoes begins by slowly introducing them to the outdoors. Start by placing them in a sheltered spot, such as a porch or a partially shaded area, for a few hours each day. Over a week, gradually increase the amount of time they are kept outdoors and the amount of sun they are exposed to. After a week of hardening off, the tomatoes should be ready to move to their final outdoor planting location.

When to plant tomatoes in zone 8

It’s generally safe to plant tomatoes outdoors when there is no risk of frost or freezing temperatures. In most climates, this means waiting until at least late spring or early summer. In zone 8, your final freeze date is around March 28th, but be mindful of your weather forecast. If it seems like you’re in for a late freeze, wait to plant your tomatoes! 

When to harvest tomatoes in zone 8

When tomatoes have turned a deep red (or the ripe color of their particular variety) and have no green spots visible, they are ripe and ready to be picked. If there are still green patches on the tomato, it has not yet ripened and should remain on the vine. The ideal way to pick ripe tomatoes is to cup the tomato in your hand and give it a gentle twist- it should come off the vine with ease. When in doubt, you can leave it on the vine an extra couple of days, or harvest the entire branch of tomatoes and allow it to ripen on the vine on your window sill.

Jeff Grayson
Garden Hobbyist
Hello! I'm Jeff, an avid gardening enthusiast. I'm based out of Colorado, where I raise as many indoor and outdoor plants as I can!