Early Girl Tomato in Zone 10B — Desert Southwest

Early Girl Tomato is a winner here in our Desert Southwest gardens for a few reasons. The early harvest means you'll be enjoying fresh tomatoes weeks before other varieties even think about ripening. Plus, their classic tomato flavor is fantastic in everything from salads to sauces, and nothing beats the satisfaction of harvesting your own homegrown produce in the middle of our mild winters.

Growing tomatoes in the Desert Southwest certainly comes with its challenges, especially the extreme heat and intense sun. But with careful timing and a few tricks, you can absolutely enjoy a bountiful harvest from your Early Girl plants. Our long 349-day growing season gives you a great head start.

To get a jump on the season, start your Early Girl Tomato seeds indoors from mid December through early January. This gives them about 6 weeks to get strong before transplanting. Use seed trays or small pots filled with a good seed-starting mix.

Keep the soil consistently moist, but not soggy. Bottom watering is a great way to avoid damping off. Place the trays in a warm spot, around 70-75°F, and provide plenty of light. Since our spring character is very-early here, you need to get a head start.

Transplant your Early Girl Tomato seedlings outdoors from late January through mid March. Before planting them in the ground, harden them off by gradually exposing them to outdoor conditions for about a week. This prevents shock.

Space the plants 24-36 inches apart in well-draining soil. Keep an eye on the weather during this time. We can still get some surprisingly cool nights or even a late frost, so be prepared to cover your plants if needed.

Early Girl Tomatoes need consistent moisture to thrive, especially in our arid climate. Aim to water deeply 2-3 times per week, providing about 1-2 inches of water each time. Stick your finger about 2 inches deep into the soil – if it feels dry, it's time to water.

Water at the base of the plant to avoid wetting the leaves, which can encourage fungal diseases in our low humidity. During the monsoon season, you may be able to reduce watering frequency, but always check the soil moisture first. Mulching around your tomato plants helps retain moisture and regulate soil temperature, which is crucial in our extreme heat.

Signs of underwatering include wilting leaves and stunted growth. Overwatering can lead to yellowing leaves and root rot. Adjust your watering schedule based on the plant's needs and the weather conditions.

Early Girl Tomatoes have an indeterminate growth habit, meaning they'll keep growing and producing fruit throughout the season. They'll need strong support to keep them off the ground and prevent the stems from breaking under the weight of the fruit.

Standard 5-foot tomato cages or sturdy stakes work well for Early Girl. Install the support at planting time to avoid damaging the roots later. As the plant grows, gently tie the stems to the support as needed to keep it upright and well-supported.

Pruning your Early Girl Tomato plants can improve airflow, promote faster ripening, and increase overall fruit production. Focus on removing the suckers that grow in the "V" between the main stem and the branches. These suckers steal energy from the plant and can create a dense, bushy plant that's more susceptible to disease.

Also, remove any yellowing or diseased leaves from the bottom of the plant to improve air circulation. As the first frost approaches in late December, you can top the plant to encourage the remaining green tomatoes to ripen.

You can expect your first harvest of Early Girl Tomatoes from mid March through late May. The fruits are ready to pick when they turn a deep red color and are slightly soft to the touch. Gently twist or snip the tomatoes from the vine, being careful not to damage the plant.

To encourage continued production, harvest the tomatoes as soon as they ripen. If a frost threatens in late December, harvest any remaining green tomatoes and bring them indoors to ripen. They'll ripen best in a single layer, not touching, in a cool dry place.

Here are some common problems you might encounter with Early Girl Tomatoes in the Desert Southwest:

• Blossom End Rot
• What it looks like: Sunken, dark brown or black leathery patch on the bottom of the fruit, usually on the first fruits of the season.
• What causes it: Calcium deficiency caused by inconsistent watering. Our dry spells followed by monsoon moisture can create this problem.
• How to fix/prevent it: Water consistently and deeply. Mulch heavily to maintain even soil moisture. Remove affected fruit.
• Early Blight
• What it looks like: Brown spots with concentric rings (target pattern) on lower leaves first, spreading upward. Leaves yellow and drop.
• What causes it: Fungal disease (Alternaria solani) that thrives in warm, humid conditions. Spreads via soil splash.
• How to fix/prevent it: Remove and destroy affected leaves. Mulch to prevent soil splash. Water at the base. Copper fungicide can slow the spread.
• Hornworms
• What it looks like: Large sections of leaves stripped overnight. Large green caterpillars with white stripes and dark droppings on leaves below.
• What causes it: Larvae of hawk moths that lay eggs on tomato plants. They can defoliate plants quickly.
• How to fix/prevent it: Handpick them (they don't bite). Bt (Bacillus thuringiensis) spray is effective and organic. Leave hornworms with white cocoons — those are beneficial parasitic wasp eggs.
• Cracking
• What it looks like: Splits in tomato skin – either concentric (circles around stem) or radial (lines radiating from stem). Can expose flesh to rot.
• What causes it: Heavy watering or rain after a dry spell. Fruit absorbs water faster than skin can expand.
• How to fix/prevent it: Water consistently to avoid the dry/wet cycle. Mulch to maintain even moisture. Harvest promptly when ripe.

Desert Southwest Specific Challenges: Our extreme heat can cause sunscald on the tomatoes, so providing some afternoon shade with shade cloth is essential. Low humidity can stress the plants, making them more susceptible to pests and diseases. The monsoon season can bring sudden downpours that lead to cracking. Watch them closely.

Companion planting can help your Early Girl Tomatoes thrive. Basil is a great companion because it repels tomato hornworms and whiteflies. Carrots improve the soil around the tomatoes and deter root-knot nematodes. Parsley attracts beneficial insects that prey on tomato pests. French marigolds repel nematodes and other harmful soil pests.

Avoid planting brassicas (like cabbage and broccoli) near tomatoes, as they can stunt tomato growth. Fennel inhibits the growth of many plants, including tomatoes. Corn can attract tomato pests and diseases, so keep them separated.