How to Pot‑On Plug Plants (Step‑by‑Step + Pro Tips)
How to Pot‑On Plug Plants (Step‑by‑Step + Pro Tips)
Get your plug plants off to a flyer with this no‑nonsense method. We’ll cover compost, the perfect first pot size, light, watering, feeding, and the simple mistakes that slow growth. For sizes and delivery expectations, see the pillar guide.
What You’ll Need
- Quality peat‑free multi‑purpose compost (+ perlite for drainage)
- 7–9 cm pots for most plugs (square pots pack benches neatly and promote stronger root‑balls)
- Watering can with fine rose or trigger mister
- Plant labels, clean snips
Step‑by‑Step Potting‑On
- Rehydrate on arrival
Stand trays in a shallow tray of water for 10–20 minutes, then drain. (Also aligns with your delivery guidance in the pillar.) - Pre‑fill pots
Lightly fill pots with moist compost; tap to settle without compacting. - Release the plug
Push from underneath the cell — don’t tug leaves. - Plant at the same depth
Drop the plug in and backfill gently; avoid burying the stem. - Water to settle
Use a fine rose; avoid washing out the compost. - Bright light, good airflow
A bright windowsill, greenhouse or grow lights prevent legginess. - Temperature
12–18 °C suits most plugs; avoid cold draughts and radiator hotspots. - First feed
Start a dilute liquid feed after 2–3 weeks once roots reach the pot edge. - Move up
When roots wrap the root‑ball, step up to 1–2 litre pots or plant out
Choosing the Right First Pot
- 7 cm pots: great for small or slow types; saves space.
- 9 cm pots: the sweet spot for most bedding/perennials — fast, sturdy growth.
- Square pots: pack tightly, encourage a tidy root cube; less wasted space.
Watering & Feeding Made Simple
- Keep compost evenly moist, not soggy; let the top 1 cm dry slightly between waterings.
- Feed little and often once growth resumes; avoid strong feeds on fresh roots.
- Good light + airflow reduce damping‑off risk.
Light & Growth Control
- If stems stretch, increase light and reduce warmth a touch.
- Turn pots weekly so plants grow evenly; pinch soft tips on bushy bedding to branch.
Potting‑On Mistakes to Avoid
- Too big a pot initially → stagnant, over‑wet compost, slow roots.
- Burying stems → rot risk in cool spring soils.
- Poor drainage → mix in perlite; use pots with clear drainage holes.
- Skipping labels → chaos at planting time!
FAQs
What pot size should I start with?
Most plugs thrive in 7–9 cm pots to root quickly without staying wet for too long.
How soon should I feed?
Wait 2–3 weeks after potting‑on, then use a half‑strength liquid feed weekly.
Do I need grow lights?
Not always, but bright, consistent light prevents leggy seedlings in early spring.
When do I move to bigger pots or plant out?
When roots reach the pot edge; then step up or plant out following Cluster 1 timings.
Call to action
Pot‑on today, plant out when the weather says so. Grab 7–9 cm pots, a peat‑free mix and perlite, then follow this routine for sturdy, transplant‑ready plugs. Link back to the pillar for sizes and delivery expectations.
