Heirloom

Katz Ruby

Matthiola incana

Photo: ruby katz · Wikimedia Commons · (CC BY-SA 4.0)

Long stems with 1 1/2-2", wine-red colored blooms. Early blooming one-cut series. Performed well in our spring, early summer, and fall trials. Good uniformity in bloom time and stem length. 55-60% double-flowering without selection; some selection possible. Plant Variety Protected. NOTE: This variety produces one flowering stem per plant. Pinching is not advisable as it will terminate flowering. Edible Flowers: The peppery, clove-like flavor of the flowers lends itself well to use as a garnish on salads, desserts, and drinks.

Harvest

90-100d

Days to harvest

📅

Sun

Full sun to partial shade

☀️

Zones

6–10

USDA hardiness

🗺️

Height

1-3 feet

📏

Planting Timeline

Zone:

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Start Indoors

Transplant

Direct Sow

Start Indoors

Transplant

Direct Sow

Showing dates for Katz Ruby in USDA Zone 7

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Katz Ruby · Zones 6–10

What grows well in Zone 7? →

Growing Details

Difficulty

Easy

SeasonWarm season annual

FlavorPeppery, clove-like flavor with subtle spice notes suitable for culinary garnishes.

Colorwine-red

Size1 1/2-2"

Zone-by-Zone Planting Calendar

Zone	Indoor Start	Transplant	Direct Sow	Harvest
Zone 1	May – June	July – August	July – September	—
Zone 2	April – May	June – July	June – August	—
Zone 11	January – January	January – February	January – March	—
Zone 12	January – January	January – February	January – March	—
Zone 13	January – January	January – February	January – March	—
Zone 3	April – May	June – July	June – August	—
Zone 4	March – April	June – June	June – July	—
Zone 5	March – April	May – June	May – July	—
Zone 6	March – April	May – June	May – July	—
Zone 7	February – March	April – May	April – June	—
Zone 8	February – March	April – May	April – June	—
Zone 9	January – February	March – April	March – May	—
Zone 10	January – January	February – March	February – April	—

Succession Planting

Stock doesn't hold well once it bolts, so succession planting is worth the extra seed cost. In zone 7, sow a first round indoors in early February for a late April transplant. Start a second round indoors in late February to early March and transplant in May. That gives you two overlapping waves of bloom before June heat shuts things down — Matthiola incana stops producing quality stems once daytime highs are consistently above 80°F, which arrives somewhere around mid-June most years here.

For a fall cut-flower window, start a third round indoors in early August and transplant in early September. Plants establish through the warm early fall and come into bloom as temperatures drop into the 60s in October and November. That fall round often yields the best stem length of the year, since nothing is racing against a heat deadline.

Complete Growing Guide

Light: Full sun (6 or more hours of direct sunlight a day), Partial Shade (Direct sunlight only part of the day, 2-6 hours). Soil: Clay, High Organic Matter, Loam (Silt), Sand. Soil pH: Alkaline (>8.0), Neutral (6.0-8.0). Drainage: Good Drainage, Moist. Height: 1 ft. 0 in. - 3 ft. 0 in.. Spread: 0 ft. 9 in. - 1 ft. 6 in.. Spacing: Less than 12 inches, 12 inches-3 feet. Growth rate: Rapid. Maintenance: Low. Propagation: Seed. Regions: Coastal, Mountains.

Harvesting

Katz Ruby reaches harvest at 90 - 100 days from sowing per Johnny's Selected Seeds. Expect 1 1/2-2" at peak. As an annual, harvest continues until frost ends the season.

Seeds will ripen in August and September.

Harvest time: Fall

Storage & Preservation

Fresh Katz Ruby flowers should be stored stem-down in a vase with fresh water at room temperature (65-70°F) away from direct sunlight and ethylene-producing fruits. In cool conditions, blooms last 7-10 days. For preservation, try air-drying by hanging bundles upside-down in a warm, dark, well-ventilated space for 1-2 weeks to create long-lasting dried arrangements. Alternatively, press flowers between parchment paper under heavy books for 2-3 weeks for crafts and decorative uses. For culinary preservation, freeze edible petals in ice cube trays with water for garnishing drinks, or dry petals on a low-temperature oven setting (150°F, 30-40 minutes) and store in airtight containers for up to 6 months.

History & Origin

Katz Ruby is open-pollinated, meaning seed saved from healthy plants will produce true-to-type offspring. Listed in the Johnny's Selected Seeds catalog.

Origin: The Coast of Europe from Spain to Greece.

Advantages

+Wine-red blooms on long stems create striking cut flower arrangements
+Reliable early blooming with excellent uniformity across spring, summer, and fall
+Over half the plants naturally produce double flowers without selection needed
+Edible flowers with peppery clove flavor work well as gourmet garnishes
+Easy to grow variety with minimal care requirements for most gardeners

Considerations

-Single flowering stem per plant limits yield compared to pinchable varieties
-Cannot pinch for branching without completely terminating the plant's flower production
-Plant Variety Protected status may restrict seed saving and propagation options
-Requires 90-100 days to bloom, making it less suitable for quick turnarounds

Companion Plants

Marigolds and sweet alyssum are the most useful neighbors for Katz Ruby stock. French marigolds (the 'Bonanza' series works well) deter aphids and whiteflies through root exudates and pull in parasitic wasps that knock back caterpillar pressure. Sweet alyssum draws hoverflies whose larvae eat aphids — worth having close by, since stock can take a real hit from green peach aphid (Myzus persicae) once warm weather arrives. Catmint and lavender are solid fillers in the same bed; neither competes aggressively for nutrients at stock's root depth, and both extend the pollinator window when you're cutting for market or the house.

Keep stock well away from fennel and black walnut. Fennel releases allelopathic compounds that stunt most neighboring plants — it's a poor companion for nearly everything in a cutting garden, and stock's shallow roots make it more vulnerable, not less. Black walnut is a different problem: juglone, the compound in its root zone and decomposing leaf litter, is potent enough to damage sensitive plants at 50–60 feet from the trunk. In our zone 7 Georgia gardens, where black walnuts turn up along fence rows and field edges with some regularity, that's a bigger practical concern than most growers expect the first time they lose a bed to it.

Plant Together

Marigolds

Repel nematodes and aphids while attracting beneficial insects

Lavender

Deters pests with strong fragrance and attracts pollinators

Nasturtiums

Act as trap crop for aphids and cucumber beetles

Sweet Alyssum

Attracts beneficial insects like lacewings and hover flies

Zinnia

Attracts butterflies and beneficial predatory insects

Cosmos

Provides habitat for beneficial insects and adds complementary colors

Catmint

Repels ants, mice, and various garden pests

Sunflowers

Attract pollinators and beneficial birds that eat pest insects

Keep Apart

Black Walnut

Produces juglone which is toxic to many flowering plants

Eucalyptus

Releases allelopathic compounds that inhibit nearby plant growth

Fennel

Inhibits growth of most garden plants through allelopathy

Troubleshooting Katz Ruby

What you'll see, why it happens, and what to do about it.

Seedlings collapse at soil level ('pinched' stem) shortly after germination or transplant

Likely Causes

Damping off (Pythium or Rhizoctonia spp.) — fungal rot triggered by soggy, poorly drained growing medium
Overwatering combined with low airflow in seed trays

What to Do

1.Water only when the top half-inch of medium is dry; bottom-water trays rather than overhead misting
2.Run a small fan near seedlings for at least a few hours daily to improve air circulation
3.If starting fresh, use a sterile seed-starting mix and clean trays — don't reuse last season's mix

White to gray powdery coating on leaves, usually appearing mid-to-late season

Likely Causes

Powdery mildew (Erysiphe cruciferarum) — common on Matthiola in humid conditions with warm days and cool nights
Crowded planting that restricts airflow between stems

What to Do

1.Space plants at least 9–12 inches apart at transplant to keep air moving
2.Apply a dilute potassium bicarbonate spray (1 tablespoon per gallon) at first sign — it won't cure advanced infection but slows spread
3.Pull and trash badly affected plants; don't compost them

Leaves develop small, irregular yellow patches that turn tan-brown with a faint halo, often on older foliage first

Likely Causes

Downy mildew (Peronospora matthiolae) — favored by cool, wet weather in early spring
Overhead irrigation that keeps foliage wet overnight

What to Do

1.Switch to drip irrigation or water at the base of plants early in the morning
2.Remove affected leaves promptly and dispose in the trash
3.Avoid planting stock in the same bed two seasons running — rotate to a different brassica-family crop or non-host

Plants bloom early with short stems and quickly go to seed, well before the 90–100 day mark

Likely Causes

Heat stress — Matthiola incana bolts when daytime temperatures consistently exceed 80°F
Transplanting too late in spring, putting plants into warming soil with no cool-season runway left

What to Do

1.In zone 7, transplant by late April at the latest so plants establish during the 60–75°F window before June heat arrives
2.Start seeds indoors in February so you have stocky 8–10 week transplants ready to go in early
3.Consider a fall planting started indoors in August — stock performs well as temperatures drop back into the 60s in October and produces longer stems than a rushed spring crop

Frequently Asked Questions

How long do Katz Ruby flowers last in a vase?▼

Katz Ruby blooms typically last 7-10 days when stored in fresh water at room temperature (65-70°F), away from direct sunlight and ripening fruits. Change the water every 2-3 days and trim stems at an angle for maximum vase life. Cool conditions extend longevity, while warm temperatures shorten it. Remove any foliage below the waterline to prevent bacterial growth.

Is Katz Ruby a good variety for beginners?▼

Yes, Katz Ruby is excellent for beginners. It's classified as Easy difficulty, performs well across spring, early summer, and fall trials, and offers good uniformity in bloom time and stem length. However, note that it produces only one flowering stem per plant and pinching will terminate flowering, so avoid that common practice.

Can you grow Katz Ruby in containers?▼

Yes, Katz Ruby can be grown in containers, particularly deep pots to accommodate the long stems. Ensure containers are at least 6-8 inches deep with good drainage. Place in full sun to partial shade (4-6+ hours minimum). Container-grown plants may need more frequent watering than in-ground plantings, especially during hot weather.

What does Katz Ruby taste like and how do you use it?▼

Katz Ruby flowers have a peppery, clove-like flavor profile, making them ideal as edible garnishes. Use them fresh on salads, desserts, and drinks for both visual appeal and subtle spice. The petals add a sophisticated touch to cocktails, cupcakes, and appetizer platters. Always confirm they're pesticide-free before consuming.

When should I plant Katz Ruby seeds?▼

Sow Katz Ruby seeds after the last frost date in your area, as they're frost-sensitive. For earlier blooms, start seeds indoors 6-8 weeks before your last frost date, then transplant seedlings outside once soil has warmed. The variety takes 90-100 days to harvest, so plan accordingly for your desired bloom season.

Why shouldn't you pinch Katz Ruby flowers?▼

Unlike many flowering plants, Katz Ruby produces only one flowering stem per plant. Pinching the growing tip—a standard technique to encourage branching—will terminate that single stem's flowering potential, significantly reducing your bloom yield. Allow the plant to grow unpinched for best results.