Sun Gold Tomato in Zone 10B — Southern California

Sun Gold tomatoes are practically candy, and here in Southern California, we can get away with growing them almost year-round. Their intense sweetness and vibrant color make them perfect for snacking straight off the vine, adding to salads, or even grilling. Few things beat the satisfaction of harvesting baskets of these golden gems from your own backyard.

Sure, SoCal throws some curveballs our way – drought, occasional heat waves, and Santa Ana winds. But with careful planning and attention, we can easily navigate these challenges and enjoy a bountiful Sun Gold harvest. Plus, our long growing season means we have about 355 days to get it right!

Starting Sun Gold tomato seeds indoors gives them a head start before our warm season kicks into high gear. Aim to sow your seeds indoors from early to late December, about six weeks before you plan to transplant them outside. This is a great time to get started since our spring comes very early.

Use seed trays or small pots filled with a good seed-starting mix. Keep the soil consistently moist (bottom watering works great!) and provide warmth and light. A heat mat and grow lights are super helpful, especially if you're in a cooler part of SoCal.

Transplant your Sun Gold seedlings outdoors from late January through late February, once they have a few sets of true leaves and the weather has settled a bit. Before planting them in the ground, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the sun and wind.

Space your plants about 24 to 36 inches apart in a sunny spot with well-draining soil. Keep an eye on the forecast for any late-season cold snaps or unexpected rain, and be ready to cover your young plants if needed.

Sun Golds are thirsty plants, especially when they're loaded with fruit. In our hot, dry SoCal climate, consistent watering is key to preventing fruit cracking and ensuring a steady harvest. During the warmer months, you'll likely need to water deeply several times a week.

Stick your finger about two inches into the soil – if it feels dry, it's time to water. Aim for about 1-2 inches of water per week, adjusting based on rainfall and temperature. Water at the base of the plant to avoid wetting the foliage, which can encourage disease in our low-to-moderate humidity.

Watch for signs of underwatering, like wilting leaves and blossom end rot, or overwatering, like yellowing leaves. A good layer of mulch around the base of your plants will help retain moisture and regulate soil temperature, which is especially helpful during our hot summers.

Sun Gold tomatoes are vigorous, indeterminate growers, which means they'll keep growing and producing all season long. They need strong support to keep them off the ground and prevent the vines from sprawling. Cages or sturdy stakes work best.

Install your support system at planting time to avoid disturbing the roots later on. As the plant grows, gently tie the main stem to the stake or weave it through the cage to keep it upright. Trust me, you'll be glad you invested in good support – these plants get BIG!

If you don't prune your Sun Golds, they'll quickly take over your entire garden! Regular pruning is essential for managing their growth and improving air circulation. Focus on removing suckers, which are the small shoots that grow in the crotch between the main stem and branches.

Pinch off these suckers early in the morning when they're small and easy to remove. Also, remove any yellowing or diseased leaves, especially those near the bottom of the plant. As the end of the season approaches (around late December), you can top the plant to encourage the remaining fruit to ripen.

Get ready for a deluge of deliciousness! You can expect your first Sun Gold harvest from late March through early May, depending on when you transplanted. The tomatoes are ready to pick when they turn a deep orange-gold color, are slightly soft to the touch, and practically fall off the vine.

Harvest regularly to encourage continued production. Sun Golds are so prolific that you'll likely be sharing them with neighbors and friends. As our first frost approaches in late December, harvest any remaining green tomatoes and let them ripen indoors. They won't be quite as sweet as vine-ripened ones, but they'll still be tasty.

Even with the best care, you might encounter a few problems with your Sun Gold tomatoes. Here are three common ones:

Cracking

• What it looks like: Splits in the tomato skin, either concentric circles around the stem or radial lines radiating from the stem.
• What causes it: Inconsistent watering, especially heavy watering after a dry spell. The fruit absorbs water too quickly, causing the skin to split.
• How to fix/prevent it: Water consistently and deeply to avoid the dry/wet cycle. Mulch around the base of the plant to maintain even soil moisture. Harvest ripe tomatoes promptly.

Over-production

• What it looks like: An overwhelming amount of tomatoes, more than you can possibly eat or give away.
• What causes it: Sun Golds are just naturally prolific!
• How to fix/prevent it: Plan ahead! Plant fewer plants than you think you need. Preserve your harvest by canning, freezing, or making sauce. Share with neighbors.

Early Blight

• What it looks like: Brown spots with concentric rings (target or bullseye pattern) on lower leaves first, spreading upward. Leaves yellow and drop.
• What causes it: A fungal disease (Alternaria solani) that thrives in warm, humid conditions. Spreads via soil splash onto lower leaves.
• How to fix/prevent it: Remove and destroy affected leaves (don't compost). Mulch to prevent soil splash. Water at the base, not overhead. Improve air circulation through spacing and pruning. Copper fungicide can slow the spread. Rotate crops yearly.

Southern California Specific Challenges: Our hot summers inland can stress tomato plants, making them more susceptible to problems. Drought and water restrictions mean we need to be extra mindful of our watering practices, focusing on deep, infrequent watering rather than shallow, frequent watering. Santa Ana winds can also dry out plants quickly, so be sure to provide extra water and protection during these events.

Companion planting can help your Sun Gold tomatoes thrive! Basil is a classic companion because it repels tomato hornworms and other pests. Carrots and parsley attract beneficial insects that prey on tomato pests. French marigolds deter nematodes and other soil-borne pests.

Avoid planting brassicas (like broccoli, cabbage, and kale) near your tomatoes, as they can stunt their growth. Fennel is also a bad companion, as it inhibits the growth of many plants. Corn is a heavy feeder and can compete with tomatoes for nutrients.