Growing Tomatoes in Santa Cruz County: A Complete Guide
Tomatoes are the heart of the summer garden, and Santa Cruz County offers nearly ideal conditions for growing them. Nearly.
Our Mediterranean climate delivers the warm days tomatoes crave, but our coastal fog, cool nights, and wildly variable microclimates mean that generic California tomato advice often falls flat here. What works in Sacramento or Los Angeles won't necessarily work in Aptos or Boulder Creek. The gardener in sunny Scotts Valley faces different challenges than someone growing in foggy westside Santa Cruz.
The good news: once you understand our local quirks, tomatoes become one of the most rewarding crops you can grow. This guide covers everything Santa Cruz County gardeners need to know, from variety selection to harvest, with specific advice for our unique growing conditions.
Understanding Our Tomato-Growing Climate
Before diving into techniques, it's worth understanding why Santa Cruz County requires a different approach than inland California.
The Coastal Influence
UC Master Gardeners note that coastal California presents unique challenges for heat-loving crops like tomatoes. Our summer fog, while keeping temperatures comfortable for humans, can limit the heat accumulation tomatoes need for optimal fruit development. Morning fog that doesn't burn off until afternoon effectively shortens our growing day.
Coastal areas (westside Santa Cruz, Live Oak, Aptos near the beach): Expect later ripening, benefit from heat-tolerant varieties that also set fruit in cooler conditions, and plan for potential late blight pressure from humidity.
Inland and valley areas (Scotts Valley, San Lorenzo Valley sunny exposures, Soquel hills): More heat means faster ripening and more variety options, but watch for sunscald and increased water needs.
Under redwood canopy (Felton, Ben Lomond canyons): Limited sun hours challenge tomato production. Focus on cherry types and early-maturing varieties, or consider container growing in the sunniest spot available.
Cool Nights and Blossom Drop
One of our biggest local challenges is cool summer nights. UC Agriculture and Natural Resources explains that tomato flowers may fail to set fruit when nighttime temperatures drop below 55°F or rise above 75°F. In many Santa Cruz County locations, summer nights regularly dip into the low 50s, causing blossom drop that frustrates gardeners who see flowers but no fruit.
This isn't a disease or deficiency. It's a physiological response to temperature. Understanding this helps you choose appropriate varieties and set realistic expectations.
Choosing Tomato Varieties for Santa Cruz County
Variety selection is the single most important decision you'll make. The wrong variety in the wrong microclimate leads to disappointment regardless of how well you tend your plants.
What to Look For
Cool-tolerance: Varieties bred to set fruit in cooler conditions outperform standard types in coastal Santa Cruz.
Early maturity: Shorter days-to-harvest means ripe tomatoes before fall weather arrives. Look for varieties maturing in 60-75 days rather than 80-90+.
Disease resistance: Our coastal humidity encourages fungal diseases. Varieties with resistance to late blight, early blight, and fusarium wilt have advantages here.
Proven Performers for Coastal Santa Cruz
These varieties have track records in cooler, foggier conditions:
'Early Girl': The workhorse of coastal California tomato growing. Early maturing (50-60 days from transplant), reliable fruit set in cool conditions, good disease resistance. Not the most complex flavor, but consistently productive when other varieties struggle.
'San Francisco Fog': Bred specifically for cool coastal conditions. Sets fruit reliably even with fog and cool nights. Medium-sized red tomatoes with good flavor.
'Stupice': Czech heirloom known for early production and cold tolerance. Small to medium red fruits with excellent flavor. One of the first to ripen.
'Oregon Spring': Developed at Oregon State University for short-season, cool climates. Sets fruit parthenocarpically (without pollination) in cool weather when other varieties drop blossoms. Medium-sized fruits.
'Glacier': Extremely early (55 days), compact plants, tolerates cool conditions well. Good for containers or small spaces.
Cherry Tomatoes: Your Insurance Policy
Cherry tomatoes generally outperform larger varieties in challenging conditions. They ripen faster, tolerate temperature fluctuations better, and produce reliably even in less-than-ideal summers.
'Sungold': The benchmark for cherry tomato flavor. Orange fruits with tropical sweetness. Vigorous, productive, and relatively tolerant of varied conditions.
'Sweet 100': Extremely productive red cherry. Vigorous vines that need strong support.
'Black Cherry': Complex, rich flavor with dusky purple-brown color. Slightly less productive than red cherries but worth growing for flavor.
'Matt's Wild Cherry': Tiny, intensely flavored red cherries. Extremely vigorous and productive. Self-seeds readily.
For Warmer Inland Microclimates
If you garden in Scotts Valley, sunny San Lorenzo Valley exposures, or other warm pockets, you have more flexibility:
'Cherokee Purple': Heirloom with complex, rich flavor. Needs warmth to perform well.
'Brandywine': Classic heirloom, considered among the best-flavored tomatoes. Late maturing and needs heat.
'San Marzano': The paste tomato standard. Needs consistent warmth for good production.
'Better Boy': Reliable hybrid with good disease resistance and classic tomato flavor.
Local Sources for Starts and Seeds
Finding good varieties locally gives you a head start:
San Lorenzo Garden Center (Santa Cruz): Good selection of starts in spring
Sierra Azul Nursery (Watsonville): Native focus but sometimes carries vegetable starts
Renee's Garden Seeds (Felton): Local seed company with excellent variety selection
Love Apple Farms (Santa Cruz Mountains): Specializes in tomatoes, offers plants and classes
UCSC Farm & Garden: Plant sales in spring
Site Selection and Soil Preparation
Tomatoes need the best spot in your garden. Compromise here and you'll struggle all season.
Sun Requirements
UC recommends at least 6-8 hours of direct sunlight for tomatoes. In Santa Cruz County's cooler microclimates, more is better. Morning sun that dries dew quickly helps prevent fungal diseases.
Evaluate your site honestly. That "sunny" spot that gets dappled afternoon light isn't sunny enough. Track actual sun hours before committing to a location. In foggy areas, southern exposure against a heat-reflecting wall or fence can make the difference between success and disappointment.
Soil Preparation
Tomatoes are heavy feeders that reward good soil preparation.
Start with a soil test. UC Cooperative Extension and private labs offer soil testing that reveals pH, nutrient levels, and organic matter content. This removes guesswork from fertilizing.
Ideal conditions:
pH 6.2-6.8 (slightly acidic to neutral)
Rich in organic matter
Well-draining but moisture-retentive
Loose texture that allows root penetration
Before planting:
Add compost. Work 2-4 inches of finished compost into the planting area. This improves soil structure, drainage, and nutrient availability.
Address pH if needed. If soil is too acidic, add garden lime. If too alkaline (less common here), add sulfur. Follow soil test recommendations.
Loosen soil deeply. Tomato roots can extend 2-3 feet down. Loosen soil at least 12 inches deep, ideally more.
In clay soils (common in parts of Santa Cruz County): Focus on improving drainage with organic matter. Raised beds can help in areas with heavy clay or poor drainage.
Planting Tomatoes
Timing and technique both matter for getting your tomatoes off to a strong start.
When to Plant
- Start seeds indoors 6-8 weeks before transplanting
- Prepare beds with compost and amendments
- Test soil if you haven't recently
- Transplant after frost risk passes and soil warms
- Install cages or stakes at planting time
- Mulch after soil has warmed
- Transplant once soil reaches 60°F consistently
- Later is better than earlier in foggy areas
- Consider row cover for extra warmth
- Establish consistent watering schedule
- Side-dress with fertilizer when flowering begins
- Begin pruning suckers on indeterminate varieties
- Peak harvest season for most varieties
- Maintain consistent watering (critical for quality)
- Monitor for late-season disease pressure
- Top plants in September to ripen remaining fruit
- Harvest all remaining fruit showing any color
- Ripen green tomatoes indoors or use in recipes
- Remove plants, clean up debris
Soil temperature matters more than air temperature. Tomatoes struggle when soil is below 60°F. Cold soil stunts growth and makes plants vulnerable to disease.
General timing for Santa Cruz County:
Coastal areas: Mid-April to early May, after soil has warmed. Later is often better than earlier here.
Inland/warmer areas: Late March to mid-April, once frost risk has passed and soil has warmed.
Don't rush. A tomato planted in warm soil in May will outperform one planted in cold soil in March. Patience pays.
Transplanting Technique
Tomatoes can root along their stems, a characteristic you can exploit for stronger plants.
Deep planting method:
Dig a hole deep enough to bury the stem up to the lowest set of healthy leaves.
Remove leaves from the portion of stem that will be buried.
Set the plant in the hole, backfill with soil, and firm gently.
Water deeply to settle soil around roots.
Trench planting method (alternative for leggy transplants):
Dig a shallow trench rather than a deep hole.
Lay the plant on its side in the trench with the top few inches of foliage above ground.
The buried stem will root along its length, and the top will curve upward toward the sun within days.
Both methods produce plants with extensive root systems that access water and nutrients more effectively.
Spacing
Proper spacing improves air circulation, reducing disease pressure, and gives each plant room to develop.
Determinate varieties: 18-24 inches apart
Indeterminate varieties: 24-36 inches apart, depending on support system
Rows: 3-4 feet apart for access
In our humid coastal climate, err toward more space rather than less. Air circulation helps prevent fungal diseases.
Supporting Your Tomatoes
All tomatoes benefit from support, and indeterminate varieties absolutely require it. Our separate trellising guide covers this in detail, but here are the basics.
Why Support Matters
Keeps foliage and fruit off the ground, reducing disease and pest problems
Improves air circulation
Makes harvesting easier
Allows plants to grow vertically, saving space
Support Options
Cages: Easy and hands-off. Commercial cages are often too flimsy for vigorous indeterminate varieties. Look for heavy-gauge wire cages or make your own from concrete reinforcing wire.
Stakes: Single stake per plant, with stems tied as they grow. Requires more attention than cages but takes less space.
Florida weave: String woven between stakes to support multiple plants in a row. Efficient for larger plantings.
Trellising: Vertical strings or netting attached to overhead support. Common in greenhouse production and works well outdoors too.
Install support at planting time to avoid disturbing roots later.
Watering Tomatoes
Consistent moisture is one of the most important factors in tomato health and fruit quality. Irregular watering causes cracking, blossom end rot, and other problems.
- Water the soil, not the leaves
- Don't water a little every day
- Deep and less frequent is best
- Don't let soil dry out completely
- Mulch to retain moisture
- Don't water overhead in evening
How Much Water
Tomatoes generally need 1-2 inches of water per week, depending on weather, soil type, and plant size. This translates to deep watering that moistens soil to at least 6-8 inches deep.
Sandy soils drain quickly and need more frequent watering. Clay soils hold moisture longer. Adjust your schedule to your specific conditions.
How to Water
Water the soil, not the foliage. Wet leaves promote fungal diseases. Drip irrigation or soaker hoses deliver water directly to the root zone where it's needed.
Water deeply and less frequently. Light, frequent watering encourages shallow roots. Deep watering encourages roots to grow down where moisture is more stable.
Water in the morning. This gives foliage time to dry before evening, reducing disease risk.
Mulch to conserve moisture. A 2-4 inch layer of organic mulch (straw, wood chips, leaves) reduces evaporation, moderates soil temperature, and suppresses weeds. Keep mulch a few inches away from stems to prevent rot.
Signs of Water Problems
Underwatering: Wilting, especially in afternoon heat. Leaves may curl or feel dry. Plants recover overnight if caught early.
Overwatering: Yellowing leaves, especially lower leaves. Plants may wilt despite wet soil (root problems). Consistently soggy soil promotes root rot.
Inconsistent watering: Cracked fruit, blossom end rot, catfacing. The damage shows up in the fruit.
Fertilizing Tomatoes
Tomatoes are heavy feeders, but more isn't always better. Excess nitrogen produces lush foliage at the expense of fruit.
Understanding Tomato Nutrition
Nitrogen (N): Promotes leafy growth. Important early in the season but excessive nitrogen later reduces fruit production.
Phosphorus (P): Supports root development and flowering. Important throughout the season.
Potassium (K): Critical for fruit development and overall plant health.
Calcium: Prevents blossom end rot. Usually adequate in soil but unavailable to plants during drought stress.
Fertilizing Strategy
At planting: Mix a balanced organic fertilizer or compost into the planting hole. Some gardeners add a handful of bone meal (phosphorus) and a crushed eggshell or two (calcium).
During growth: Side-dress with compost or balanced fertilizer when plants begin flowering. Avoid high-nitrogen fertilizers after flowering begins.
What to use: Organic options like fish emulsion, kelp meal, and composted manure release nutrients slowly and improve soil health. Synthetic fertilizers work but don't build soil over time.
Container tomatoes: Need more frequent fertilizing than in-ground plants because nutrients leach out with watering. Feed every 2-3 weeks with diluted liquid fertilizer.
Avoiding Blossom End Rot
Blossom end rot appears as a dark, sunken area on the bottom of the fruit. It's caused by calcium deficiency in the developing fruit, usually due to inconsistent watering rather than lack of calcium in soil.
Prevention: Consistent watering is the primary solution. Mulching helps maintain even soil moisture. Avoid over-fertilizing with nitrogen, which promotes rapid growth that can't keep up with calcium uptake.
Pruning and Maintenance
Pruning decisions depend on whether you're growing determinate or indeterminate varieties.
Determinate vs. Indeterminate
Determinate varieties grow to a set size, flower and fruit over a concentrated period, then decline. They need minimal pruning. Removing suckers can actually reduce harvest.
Indeterminate varieties grow and produce continuously until frost. They benefit from selective pruning to manage size and improve fruit quality.
Pruning Indeterminate Tomatoes
Suckers are shoots that grow in the angle between the main stem and branches. Left alone, they become full branches.
To prune or not:
Removing suckers directs energy toward fewer, larger fruits
Leaving suckers produces more but smaller fruits
A moderate approach removes suckers below the first flower cluster and leaves those above
How to remove suckers: Pinch small suckers (under 2 inches) with your fingers. Cut larger ones with clean pruners. Remove in the morning when plants are turgid.
Other maintenance:
Remove lower leaves as plants grow, especially any touching the ground (disease prevention)
Remove yellowed or diseased leaves promptly
Late in the season, "top" plants (remove growing tips) to direct energy into ripening existing fruit
Managing Pests and Diseases
Santa Cruz County's climate favors certain pests and diseases. Vigilance and early intervention prevent small problems from becoming crop failures.
Common Pests
Tomato hornworm: Large green caterpillar that can strip foliage quickly. Hand-pick and destroy, or leave if you see white cocoons attached (those are parasitic wasp eggs that will control future generations).
Aphids: Small soft-bodied insects that cluster on new growth. Strong water spray dislodges them. Encourage beneficial insects like ladybugs. Serious infestations can be treated with insecticidal soap.
Tomato fruitworm (corn earworm): Caterpillar that bores into fruit. Hand-pick if seen. Bt (Bacillus thuringiensis) is an organic control.
Whiteflies: Tiny white flying insects on leaf undersides. Yellow sticky traps monitor and reduce populations. Insecticidal soap for heavy infestations.
Common Diseases
Early blight: Brown spots with concentric rings on lower leaves, progressing upward. Remove affected leaves. Improve air circulation. Fungicides can help prevent spread.
Late blight: Gray-green water-soaked spots that rapidly turn brown and spread to stems and fruit. The disease that caused the Irish Potato Famine. More common in cool, wet conditions. Remove and destroy (don't compost) affected plants immediately. Can devastate entire plantings quickly.
Powdery mildew: White powdery coating on leaves. More common late in the season. Improve air circulation. Sulfur-based fungicides can help.
Fusarium and Verticillium wilt: Soil-borne fungal diseases that cause wilting and death. Plant resistant varieties (look for "F" and "V" in variety descriptions). Rotate crops.
Disease Prevention
Crop rotation: Don't plant tomatoes in the same spot more than once every 3-4 years
Air circulation: Proper spacing and pruning
Water management: Drip irrigation, morning watering, avoid wetting foliage
Sanitation: Remove diseased material promptly, clean tools between plants
Resistant varieties: Choose varieties with disease resistance appropriate to your conditions
Harvesting Tomatoes
The reward for all your work. Knowing when and how to harvest maximizes flavor and extends your enjoyment.
Ripeness Indicators
Ripe tomatoes show full color for their variety (red, pink, yellow, orange, purple, or green for green-when-ripe types) and yield slightly to gentle pressure. The fruit should release easily from the stem with a gentle twist.
Don't wait too long. Overripe tomatoes lose flavor and texture, attract pests, and may crack or fall from the plant.
Harvesting in Cool Climates
In coastal Santa Cruz, tomatoes often ripen slowly or unevenly. Several strategies help:
Harvest at "breaker" stage: When tomatoes show the first blush of color change, they've reached physiological maturity and will ripen off the vine with full flavor. This gets fruit away from pests and reduces cracking from late-season rains.
Ripen indoors: Place breaker-stage tomatoes in a single layer at room temperature out of direct sun. They'll ripen in a few days to a week. A banana nearby speeds the process (ethylene gas).
End-of-season strategies: When frost threatens or plants are declining, harvest all tomatoes showing any color change. Green tomatoes can be ripened indoors (slowly) or used in recipes.
Storage
Never refrigerate ripe tomatoes. Cold temperatures destroy flavor compounds. Store at room temperature and use within a few days of full ripeness.
Slightly underripe tomatoes: Can be held at cool room temperature (55-70°F) for longer storage.
Excess harvest: Process into sauce, salsa, or canned tomatoes. Freeze whole tomatoes for cooking (texture suffers but flavor remains).
Troubleshooting Common Problems
Blossom Drop
Flowers fall off without setting fruit.
Causes: Night temperatures below 55°F or above 75°F. Excessive nitrogen. Drought stress. Heavy fruit load.
Solutions: Choose cool-tolerant varieties. Ensure consistent watering. Avoid excessive nitrogen fertilizer. In most Santa Cruz locations, cool nights are the primary cause, and variety selection is the main solution.
Cracking
Cracks radiating from the stem or in concentric circles around the fruit.
Causes: Inconsistent watering, especially heavy rain or irrigation after dry period.
Solutions: Consistent watering. Mulch. Harvest before full ripeness during rainy periods.
Blossom End Rot
Dark, sunken, leathery spot on the bottom of fruit.
Causes: Calcium deficiency in developing fruit, usually from inconsistent watering.
Solutions: Consistent watering. Mulch. Avoid over-fertilizing with nitrogen. Once affected, fruit won't recover, but subsequent fruit may be fine if watering improves.
Catfacing
Misshapen fruit with scars and cavities.
Causes: Cold temperatures during flowering. Excessive nitrogen.
Solutions: Plant after soil and air have warmed. Avoid heavy nitrogen.
Poor Fruit Set
Plants flower but don't produce fruit.
Causes: Temperature extremes. Excessive nitrogen. Insufficient pollination.
Solutions: Choose appropriate varieties. Avoid excessive nitrogen. In most cases, temperature is the issue in our climate.
Month-by-Month Tomato Calendar for Santa Cruz County
February-March: Start seeds indoors (6-8 weeks before transplanting). Prepare beds with compost.
April: Transplant after soil warms (mid-April for coast, late March for inland). Install supports.
May: Transplant remaining plants. Begin regular watering and mulching. Watch for early pest problems.
June: Side-dress with fertilizer when plants flower. Prune indeterminate varieties. Monitor for disease.
July-August: Peak harvest for most varieties. Consistent watering critical. Continue pest and disease monitoring.
September: Harvest continues. Late-season disease pressure may increase. Consider topping plants to ripen remaining fruit.
October: Harvest remaining fruit before frost or cold rain. Pull plants after harvest. Clean up debris to reduce overwintering pests.
Frequently Asked Questions
Why won't my tomatoes turn red?
Likely temperature-related. Tomatoes ripen best between 68-77°F. Above 85°F, red pigment doesn't develop. Below 50°F, ripening stalls. In cool coastal areas, harvest at breaker stage and ripen indoors.
Why do my tomato plants have lots of leaves but no fruit?
Too much nitrogen fertilizer promotes vegetative growth at the expense of fruiting. Also, cool night temperatures cause blossom drop. Switch to lower-nitrogen fertilizer and choose cool-tolerant varieties.
What's the best tomato variety for Santa Cruz?
'Early Girl' is the reliable standard for coastal conditions. 'Sungold' cherry is nearly foolproof and delicious. For warmer inland areas, you have more flexibility with heirloom and main-season varieties.
Can I grow tomatoes year-round in Santa Cruz County?
Not outdoors. Tomatoes need warmth and day length that our winters don't provide. Greenhouse growing can extend the season but even then, winter production is limited.
Should I prune my tomato plants?
Depends on the type. Indeterminate varieties benefit from selective sucker removal. Determinate varieties should not be heavily pruned. When in doubt, less pruning is safer.
How do I prevent blossom end rot?
Consistent watering is the answer in almost all cases. The problem is calcium uptake, not calcium availability. Mulch, drip irrigation, and regular deep watering prevent the moisture fluctuations that cause blossom end rot.
My tomato leaves are turning yellow. What's wrong?
Many possibilities: overwatering, underwatering, nitrogen deficiency, natural aging of lower leaves, or disease. Yellow lower leaves are often normal as plants age. Yellowing throughout the plant suggests watering issues or disease.
Growing Great Tomatoes Here
Santa Cruz County isn't the easiest place to grow tomatoes, but it's far from the hardest. Our challenges are specific and manageable: cool nights, coastal fog, and disease pressure from humidity. Address those with smart variety selection, good soil preparation, consistent watering, and appropriate expectations, and you'll harvest delicious tomatoes every summer.
Start with proven performers like 'Early Girl' and 'Sungold' while you learn your microclimate's quirks. As you gain experience, experiment with heirlooms and longer-season varieties. Pay attention to what works in your specific garden, because conditions can vary dramatically even within a few blocks.
The tomatoes you grow yourself, picked ripe from your own garden, will taste better than anything you can buy. That's worth the effort of learning to grow them well.
Free Gardening Resources
Know Your Microclimate Worksheet: Understand your specific Santa Cruz County growing conditions
Seasonal Planting Calendar: Month-by-month guidance for Santa Cruz County
Tomato Variety Selector: Find the right varieties for your garden
Related Tomato Articles
Growing Tomatoes in Santa Cruz County
Growing Tomatoes in Containers
Heirloom Tomatoes for Santa Cruz
Determinate vs Indeterminate Tomatoes
Watering Tomatoes in Santa Cruz
Tomato Fertilizing + Soil Prep
Tomato Problems + Troubleshooting
