How to Grow Scarlet Gem
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Scarlet Gem
Solanum lycopersicum 'Scarlet Gem'
vegetableScarlet Gem is a compact, determinate cherry tomato variety that produces abundant small, bright red fruits with excellent flavor. This dwarf cultivar is ideal for container gardening and small spaces, reaching only 12-18 inches in height. The plants are prolific producers, offering continuous harvests throughout the season.
When should you plant Scarlet Gem in your zone?
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Example Scarlet Gem timeline · Pittsburgh, PA (Zone 6b)
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Plant Scarlet Gem
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Scarlet Gem
Around Jun 21≈ 65 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Scarlet Gem dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-11; grow as annual in cooler zones, or indoors/greenhouse in zone 2
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Get my Scarlet Gem timeline →Growth Stages
Seedling
2-3 weeksTiny plants with 2 cotyledons (seed leaves) followed by first true leaves. Growth is slow initially.
Provide bright light (14-16 hours daily under grow lights). Keep soil moist but not waterlogged. Maintain 70-75°F temperature. Bottom heat accelerates germination.
Vegetative Growth
4-6 weeksPlants develop sturdy stems, multiple sets of true leaves, and a compact, bushy form. Plants reach 6-12 inches tall.
Thin seedlings early or pot up individually. Reduce watering slightly after sprouting. Apply balanced fertilizer every 2 weeks. Harden off transplants before planting outdoors.
Flowering
3-4 weeksSmall yellow flowers appear in clusters along the main stem and side shoots. The plant may be 10-16 inches tall.
Maintain consistent watering; inconsistent moisture causes blossom end rot and flower drop. Switch to lower nitrogen, higher phosphorus fertilizer (like 5-10-10). Gently shake plants midday to aid pollination.
Fruiting
4-6 weeks per setMarble-sized green fruits develop at flower clusters, gradually enlarging and turning bright scarlet red over 2-3 weeks.
Maintain steady watering without oversaturation. Provide minimal pruning; Scarlet Gem doesn't require extensive staking but may benefit from light support. Feed with balanced or fruit-promoting fertilizer.
Harvest & Production
6-12 weeks (until frost or plant decline)Plant produces abundant ripe red cherry tomatoes, typically 1-2 inches in diameter. Continuous flowering and fruiting throughout warm season.
Harvest ripe fruits regularly to encourage more production. Keep picking even if not needed; this signals the plant to produce more. Continue watering and feeding throughout season.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick large caterpillars early morning or evening. Use Bacillus thuringiensis (Bt) for smaller infestations. Plant dill and parsley to attract parasitic wasps.
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Spray forcefully with water to dislodge. Use insecticidal soap or neem oil. Introduce ladybugs and parasitic wasps.
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Increase humidity and spray foliage with water. Use neem oil or miticide in severe cases. Avoid excessive nitrogen fertilizer.
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Remove lower infected leaves. Improve air circulation. Mulch to prevent soil splash. Apply copper or chlorothalonil fungicide weekly. Water at soil level only.
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Remove and destroy infected foliage immediately. Use preventive fungicides (copper, chlorothalonil) in humid conditions. Ensure good air circulation.
Uses
Fresh eating and salads
CulinaryScarlet Gem tomatoes are prized for their sweet, rich flavor and ideal snack size. Perfect for salads, antipasto, and fresh eating straight from the vine. [source]
Cooking & sauce making
CulinaryCan be roasted whole, used in pasta sauces, or stewed. Their natural sweetness makes them excellent for marinades and reductions. [source]
Nutritional & antioxidant benefits
MedicinalRich in lycopene, vitamins C and K, potassium, and antioxidants. Lycopene, the compound giving tomatoes their red color, has been studied for cardiovascular health benefits. [source]
Container and ornamental gardening
HouseholdThe compact size and prolific fruiting make Scarlet Gem an excellent choice for patio containers, window boxes, and small-space gardens. Attractive for both edible and aesthetic purposes. [source]
Seed saving
CraftAs a true variety, Scarlet Gem seeds come true from fruit. Home gardeners can easily save seeds from ripe fruits for next season's planting. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Pick fruits when fully red and slightly soft to touch, usually 6-8 weeks after flowering. Harvest regularly to maintain productivity. Fruits can be picked at 'breaker stage' (just showing color) and ripened indoors if needed. Store at room temperature; refrigeration diminishes flavor. Cherry tomatoes continue producing until first frost.
Fun Facts
- 🌱 Scarlet Gem is a determinate variety, meaning it grows to a fixed height and produces most of its fruit within a concentrated period, making it perfect for successive plantings every 2-3 weeks for continuous harvests.
- 🌱 Cherry tomatoes like Scarlet Gem have higher sugar content (Brix value of 8-10+) compared to larger beefsteak varieties, explaining their concentrated sweetness and candy-like flavor.
- 🌱 Scarlet Gem was introduced in the 1950s and remains a favorite heirloom variety, prized by home gardeners for its reliability, abundance, and superior taste compared to many modern hybrids.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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