First — what is a plug?
A plug is a young seedling started in a small cell — roughly the size of a thumb. They're tender little starts, not full-grown plants. They need to go in the ground within the next few days so the roots have room to grow and don't dry out.
Prep Your Soil
- Loosen the bed 10–12 inches deep so roots can run. Cut flowers love loose, well-drained soil.
- Spread 2–3 inches of finished compost over the bed and work it into the top 6–8 inches. This is the single most important step — it feeds the soil, improves drainage, and holds moisture.
- Heavy clay? (common in Utah) Add another inch of compost plus a little coarse sand or aged bark to open it up.
- Optional: mix in a balanced granular organic fertilizer (a 4-4-4 or 5-5-5) at the bag rate, roughly 1–2 lbs per 100 sq ft.
- The easy rule: 2–3 inches of compost, worked into the top 6 inches, once a season. Hard to mess up.
Want a quick reference to share or print? Open the Soil Prep & Feeding card →
Watering
- Bottom-water morning and night until you transplant. Set the cell tray in a tray of water for a few minutes, then drain — never let them sit in standing water.
- Plugs dry out fast because the cells are so small. Check moisture twice a day.
- Once planted in the ground, water deeply at the base — not overhead. Aim for a deep soak 2–3× a week rather than a shallow daily sprinkle.
Hardening Off
- These plugs have been hardening off for several days — they're ready for outdoor conditions but still tender. Bring them in or cover them if temps drop below 35°F.
- If you can't plant right away, set them in a sheltered, bright spot — morning sun, afternoon shade. Avoid harsh midday sun and strong wind for the first few days.
Planting Out
- These are ready to go in the ground right now — just watch the forecast for any late frost.
- If you can't plant within a few days, leave them in the six-pack cell and keep bottom-watering morning and night until you can.
- Space about 9–12" apart. Water in well at planting and keep evenly moist the first week.
- Pinch snapdragons at 6" tall for more branches and more blooms. Do not pinch lisianthus.
Feeding Through the Season
- At planting: the balanced granular from Step 1, or a handful of slow-release food.
- Weeks 1–4 (getting established): go light. A diluted fish/kelp or balanced liquid feed every 2 weeks. Too much nitrogen early gives you leaves, not flowers.
- Once buds appear (about June on): switch to a bloom food — lower nitrogen, higher phosphorus & potassium (something like a 3-9-4) every 2 weeks.
- Little and often beats one big dose. Keep it consistent and your plants will reward you.
Cold Weather Watch
Utah late-spring frosts are common. If a cold snap is in the forecast (under 35°F), cover plants with a frost cloth, sheet, or upside-down pot overnight. Remove the cover in the morning so they get sun.
A note on zinnias
Your Sunset Mix kit includes zinnia seeds, but plant those separately. Zinnias grow 4–5 ft tall and will shade out the rest of the bed. Find them their own sunny spot — back of a garden bed, along a fence line, or a dedicated cutting row.
Planning where everything goes?
Three suggested arrangements for your 72 plugs — Confetti, Color Drift, and Patchwork Clusters. Visual maps you can plant by.
View Planting LayoutsQuestions?
Reach out anytime via Instagram — happy to help troubleshoot, share photos of how mine are doing, or talk shop about cut flowers.
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