Step‑by‑Step: How to Pot‑On Plug Plants

Potting‑on plug plants is simple once you know the basics. As soon as roots hold the compost together, move plugs into 9–10.5cm pots with fresh peat‑free compost, water well, and keep somewhere bright and frost‑free for 7–10 days. This beginner‑friendly guide walks you through every step for strong, fast-rooting young plants.

What You’ll Need

• 9–10.5cm clean pots (or next size up for XL plugs)
• Fresh peat‑free multipurpose compost
• Perlite (optional for extra drainage)
• Watering can with fine rose / spray mister
• Labels + pencil
• Gloves and a clean work surface

1. Pre‑Water the Plugs

• Water plugs 30–60 minutes before you begin
• Helps the rootball stay intact

2. Prepare Your Pots

• Fill pots 2–3cm below the rim
• Tap the pot gently to settle the compost
• Do not compact the soil

3. Make the Planting Hole

• Use your finger or a dibber
• Hole should be just deep enough to fit the plug

4. Remove the Plug Carefully

• Gently squeeze the cell to release the plug
• Lift by a leaf, not the stem
• Keep the rootball intact

5. Position the Plug

• Set the plug so its compost surface sits just below the new compost line
• Fill around the sides and firm gently

6. Water Thoroughly

• Water until excess drains from the base
• Allow pots to drain fully
• Label with variety + date

Aftercare: First 14 Days

Light

• Bright, indirect light
• Or lightly shaded greenhouse bench

Temperature

• Keep frost‑free, ideally above 7°C at night

Watering

• Keep compost evenly moist
• Never waterlog
• Check daily

Feeding

• Begin feeding 10–14 days after potting if growth is slow

Hardening Off

• Start after 1 week
• Gradually expose to outdoor conditions over 7–10 days

Common Mistakes (and How to Fix Them)

Burying the Stem Too Deep

• May cause rot
• Re‑pot so stem is above the compost surface

Overwatering

• Let top 1cm of compost dry before watering again

Full Sun Too Early

• Young plants scorch easily
• Provide light shade for the first week

Skipping Labels

• Always label — avoids mix‑ups later

Troubleshooting Quick Guide

• Wilting: Move to shade, mist lightly, check drainage
• Yellow leaves: Likely overwatering or lack of nutrients
• Roots circling pot: Time to pot‑on again

FAQs

When should I pot-on plug plants?

As soon as roots hold the compost together and the plug lifts cleanly.

Do I need to pinch out tips?

Yes for many bedding plants — pinch after 2–3 weeks for bushier growth.

What compost is best?

Peat‑free multipurpose compost with added perlite.

How soon can plug plants go outside?

Usually 10–14 days after potting-on, once hardened off.