Atomic Grape
Solanum lycopersicum 'Atomic Grape'
A stunning cherry tomato that delivers incredible flavor in beautiful purple and red striped packages. These elongated fruits offer an exceptional sweet-tart balance that makes them irresistible for fresh eating. The vigorous indeterminate vines produce prolific harvests of these colorful conversation-starters throughout the season.
Harvest
70-80d
Days to harvest
Sun
Full sun
Zones
10–11
USDA hardiness
Height
1-10 feet
Planting Timeline
Showing dates for Atomic Grape in USDA Zone 7
All Zone 7 tomato →Zone Map
Click a state to update dates
Atomic Grape · Zones 10–11
Growing Details
Zone-by-Zone Planting Calendar
| Zone | Indoor Start | Transplant | Direct Sow | Harvest |
|---|---|---|---|---|
| Zone 3 | April – April | June – July | — | September – October |
| Zone 4 | March – April | June – June | — | August – October |
| Zone 5 | March – March | May – June | — | August – October |
| Zone 6 | March – March | May – June | — | August – October |
| Zone 7 | February – March | April – May | — | July – September |
| Zone 8 | February – February | April – May | — | July – September |
| Zone 9 | January – January | March – April | — | June – August |
| Zone 10 | January – January | February – March | — | May – July |
| Zone 1 | May – May | July – August | — | October – August |
| Zone 2 | April – May | June – July | — | September – September |
| Zone 11 | January – January | January – February | — | April – June |
| Zone 12 | January – January | January – February | — | April – June |
| Zone 13 | January – January | January – February | — | April – June |
Complete Growing Guide
Atomic Grape tomatoes should be started indoors 6-8 weeks before your last spring frost date. Sow seeds ¼ inch deep in seed-starting mix and maintain soil temperatures around 70°F for germination. Once seedlings develop their first true leaves, provide 14-16 hours of bright light daily to prevent leggy growth. Harden off transplants over 7-10 days before moving them outdoors about a week after your last frost, when soil has warmed to at least 60°F.
Space Atomic Grape plants 24-36 inches apart in nutrient-rich, well-draining soil amended with compost or aged manure. These vigorous indeterminate vines will stretch 6-10 feet or more, so prepare sturdy trellising or caging systems at planting time. Plant slightly deeper than the nursery pot allows—tomatoes will develop roots along buried stems, creating stronger plants. Choose a location receiving at least 8 hours of direct sun daily, which is essential for developing the variety's signature purple-red striped coloring and balanced sweet-tart flavor.
Water deeply and consistently, aiming for 1-2 inches per week depending on weather. The most critical issue specific to Atomic Grape is susceptibility to blossom-end rot, which appears as dark, sunken spots on fruit. This calcium deficiency disorder is triggered by inconsistent moisture rather than actual calcium lack. Maintain even soil moisture without waterlogging, and mulch around plants to regulate moisture levels. Feed every 2-3 weeks with balanced fertilizer once flowering begins, then switch to lower-nitrogen formulas to encourage fruiting rather than excessive vine growth.
Atomic Grape's prolific nature means regular pruning of suckers maximizes fruit production and air circulation, reducing disease pressure. Remove shoots growing between the main stem and branches, especially on lower parts of the plant. This variety faces particular pressure from tomato hornworms and spider mites during hot summers—scout plants regularly and remove hornworms by hand or treat with spinosad if populations explode. Watch for early blight on lower foliage, removing affected leaves promptly and improving air flow. Septoria leaf spot also threatens this variety, so avoid overhead watering and water only at soil level early in the morning.
Most gardeners underestimate the vigor of indeterminate varieties like Atomic Grape and fail to provide adequate support structures. These plants don't stop growing and producing; they'll collapse under fruit weight and poor air circulation without proper trellising. Invest in sturdy stakes, cages, or string systems from planting day forward. With 70-80 days to first harvest and season-long production, Atomic Grape rewards consistent care with waves of those stunning striped gems. Succession planting at 3-week intervals extends your harvest window if you have space for multiple plants.
Harvesting
Harvest Atomic Grape tomatoes when they display their characteristic purple-red striping over a deep red base, as this dual-color pattern indicates peak sugar development and the complex sweet-tart flavor the variety is known for. The fruits should feel slightly yielding to gentle pressure rather than rock-hard, and individual tomatoes typically reach their ideal size of about one inch in length. Because these indeterminate vines produce continuously throughout the season, plan for successive harvests every few days rather than a single picking; leaving ripe fruit on the vine too long will redirect plant energy away from new flower development. A valuable timing tip: harvest in the early morning when fruits are coolest, as this preserves their delicate skin and extends their storage life by several days compared to afternoon picking.
The fruits are smooth, shiny, glossy, and are classified as berries. The size, shape, and color will vary depending on the variety or cultivar. The color of the fruits may be red, yellow, orange, green, purple, or pink. The fruits may contain over 100 yellow to light brown seeds.
Color: Gold/Yellow, Green, Orange, Pink, Purple/Lavender, Red/Burgundy, Variegated. Type: Berry. Length: > 3 inches. Width: > 3 inches.
Garden value: Edible, Showy
Harvest time: Fall, Summer
Edibility: The fruits or berries of the tomato are edible. They may be eaten raw, cooked, dried, or processed. They are a rich source of Vitamin A, Vitamin C, folic acid, and antioxidants. Lycopene is an antioxidant that gives the tomato its rich red color. Many plants will drop fruit when ripe or the fruit will come off easily. Tomatoes will continue to ripen once picked. Store them at room temperature.
Storage & Preservation
Store freshly harvested Atomic Grapes at room temperature away from direct sunlight to preserve their complex flavor profile; they'll keep for up to two weeks this way. For longer storage, refrigerate at 50–55°F in a breathable container, extending shelf life to three weeks. Avoid sealing them in plastic, which traps moisture and causes splitting.
These small fruits freeze well whole on a tray before bagging, making them convenient for winter cooking. For preservation, freezing works best if you plan to use them in sauces or soups where texture matters less. Drying concentrates their fruity-sweet character beautifully—use a low-temperature dehydrator or oven method for intensely flavored gems. Fermentation is also worthwhile; their balanced acid-sugar ratio ferments predictably.
Because of their small size and thin skin, Atomic Grapes don't can as whole fruits reliably, so reserve canning for sauces or salsas. When seed-saving, allow a few fruits to fully ripen and soften on the vine before fermentation extraction for best germination rates.
History & Origin
The origins of Atomic Grape remain somewhat obscure in formal horticultural documentation, though the variety exemplifies the modern trend of breeding visually striking cherry tomatoes with complex flavor profiles. As an indeterminate striped cherry type, it likely descends from heirloom purple and red striped tomato lines that gained popularity among home gardeners and specialty seed companies in the early 2000s. The variety's name and marketing suggest a relatively recent introduction by a seed company specializing in ornamental and gourmet tomatoes, though the specific breeder and year of introduction are not well-documented in public breeding records. Its characteristics align with contemporary breeding objectives emphasizing both aesthetic appeal and flavor intensity in specialty market tomatoes.
Origin: Peru
Advantages
- +Stunning purple-red striped appearance makes these fruits true garden conversation starters.
- +Exceptional sweet-tart flavor with fruity complexity surpasses most standard cherry tomato varieties.
- +Prolific indeterminate vines produce abundant harvests throughout the entire growing season.
- +Quick 70-80 day maturity allows multiple succession plantings in shorter growing regions.
Considerations
- -Susceptible to both early and late blight, requiring vigilant disease management practices.
- -Vigorous indeterminate growth demands consistent staking, pruning, and substantial garden space.
- -Multiple pest vulnerabilities including hornworms and spider mites necessitate regular monitoring.
- -Moderate difficulty level means less forgiving for beginning or inexperienced tomato growers.
Companion Plants
Basil and marigolds are worth planting within 12–18 inches of Atomic Grape. French marigolds (Tagetes patula) produce alpha-terthienyl in their roots, which suppresses root-knot nematodes — a real concern in any bed that's been running tomatoes for more than a couple of seasons. Basil shares similar water and sun needs, stays shallow-rooted so it doesn't crowd out the tomatoes, and honestly, you're going to want it at arm's reach for harvest anyway. Nasturtiums are useful as a trap crop: aphids will colonize them preferentially, pulling pressure off the Atomic Grape before it sets fruit.
Fennel is allelopathic to most vegetables and tomatoes are particularly sensitive — keep it out of the bed entirely, not just a few feet away. Black walnut (Juglans nigra) produces juglone, a compound that interferes with tomato root respiration; even mature trees 50–60 feet away can push enough juglone through the soil to stunt or kill plants. Brassicas are less dramatic but still a bad fit: they're heavy feeders competing for the same 6.2–6.8 pH soil window, and they'll slow Atomic Grape down during the first 30 days when establishment matters most.
Plant Together
Basil
Repels aphids and whiteflies, may improve flavor
Marigold
Deters nematodes and aphids with natural compounds
Carrots
Helps loosen soil for tomato roots, doesn't compete for nutrients
Parsley
Attracts beneficial insects like hoverflies that eat aphids
Peppers
Similar growing requirements and can share space efficiently
Nasturtiums
Acts as trap crop for aphids and cucumber beetles
Oregano
Repels various pests and may enhance tomato flavor
Chives
Repels aphids and may help prevent fungal diseases
Keep Apart
Walnut Trees
Produces juglone toxin that severely stunts tomato growth
Fennel
Inhibits growth of most garden plants through allelopathy
Brassicas
Compete for similar nutrients and may stunt tomato development
Nutrition Facts
Per 100g serving. % Daily Value based on 2,000 calorie diet. Source: USDA FoodData Central (FDC #321360)
Pests & Disease Resistance
Resistance
Good disease tolerance including resistance to tobacco mosaic virus
Common Pests
Tomato hornworm, aphids, whiteflies, spider mites
Diseases
Early blight, late blight, fusarium wilt, septoria leaf spot
Troubleshooting Atomic Grape
What you'll see, why it happens, and what to do about it.
Lower leaves developing dark brown spots with yellow halos, working up the plant from the soil line — typically showing up 40-50 days after transplant
Likely Causes
- Early blight (Alternaria solani) — a soil-borne fungus that splashes onto foliage during rain or overhead watering
- Septoria leaf spot (Septoria lycopersici) — looks similar but spots are smaller with a white center and dark border
What to Do
- 1.Strip and trash (don't compost) any affected leaves as soon as you see them
- 2.Lay 3-4 inches of straw mulch under the plant to stop soil splash from reaching the lower canopy
- 3.Rotate this bed out of nightshades for at least 2 seasons — both pathogens overwinter in the soil
Plant wilts during the day and doesn't recover overnight, with no obvious root damage or dry soil — fruit may still look fine early on
Likely Causes
- Fusarium wilt (Fusarium oxysporum f. sp. lycopersici) — a soil-borne fungus that colonizes the vascular system; cutting the stem near the base will show brown discoloration inside
- Southern bacterial wilt (Ralstonia solanacearum) — wilting is sudden and total; a stem cross-section dropped in water will ooze milky bacterial strands
What to Do
- 1.Dig up and destroy affected plants including as much root mass as you can — do not compost them
- 2.As NC State Extension notes, relocating your tomato bed entirely is more effective than in-bed rotation for soilborne wilts; containers with fresh mix are a reliable workaround
- 3.For future plantings, consider grafted transplants onto disease-resistant rootstock, which NC State Extension's AG-675 covers specifically for fusarium and bacterial wilt scenarios
Frequently Asked Questions
How long does Atomic Grape tomato take to grow?▼
Can you grow Atomic Grape tomatoes in containers?▼
What does Atomic Grape tomato taste like?▼
Is Atomic Grape tomato good for beginners?▼
When should I plant Atomic Grape tomato seeds?▼
How do you know when Atomic Grape tomatoes are ripe?▼
Growing Guides from Wind River Greens
Where to Buy Seeds
Sources & References
External authority sources used in compiling this guide.
See the Methodology page for how this data is sourced, what's AI-assisted, and known limitations.