Delphiniums belong on a patio when the pot is large, drains, and sits in full sun. Compact Magic Fountain types stay upright there; a six-foot Pacific in a light tub is the plant that tips.
A large drained pot in full sun
| Factor | Recommended | Avoid |
|---|---|---|
| Size | At least 12–16 inches wide and as deep as it is wide for a compact type; a heavy barrel for a tall spike | A 6-inch cup, a hanging basket, or a shallow bowl |
| Mix | Bagged potting mix plus grit or perlite; keep it moist, not waterlogged | Garden soil packed into a sealed pot |
| Type | Compact Magic Fountain or short Chinese sprays | A Pacific Giant in a light plastic tub |
A drained patio pot is a real home for a compact delphinium, as long as the vessel is heavy enough to stay upright when the spike loads. [1]
Can you grow delphiniums in pots?
Yes, in a large drained container in full sun. Compact types are the easier patio plants.
How big should the pot be?
At least 12–16 inches wide and as deep as it is wide for one compact plant. A tall Pacific type wants a heavy barrel or the ground.
How to pot a delphinium
- Choose a pot at least 12–16 inches wide and as deep as it is wide, with a drainage hole. Compact types use the smaller end; a Pacific tower needs a heavy barrel or the ground.
- Cover the hole with mesh so mix does not wash out. Do not fill the bottom with gravel.
- Fill with bagged potting mix plus grit or perlite. Do not pack garden soil. [2]
- Slide the plant out without a tool. Loosen matted roots. Set the crown level with the mix, just below the rim.
- Water once until water leaves the hole. Empty the saucer after 20 minutes.
- Set the pot in full sun with a wall or fence on the windward side. If the type is tall, put a ring in now.
One plant fills a 14-inch pot. Wear gloves when you pot — sap can irritate skin, and every part is toxic if eaten.
Compact Magic Fountain vs tall Pacific
Compact Magic Fountain types are the easier patio plants. Magic Fountain Lavender and Mini Stars hold in a 12–16 inch pot without needing a barrel, because the spike stays around three feet instead of six.
Which delphinium for a patio pot?
Start with a compact Magic Fountain or a short Chinese type. Tall Pacific spikes lodge in a light tub; give those a heavy barrel, or plant them in the ground.
Tall Pacific and elatum types such as Galahad and Faust can flower in a pot only if the tub is heavy and wide enough to take a cane without tipping. [3] Wind catches a six-foot hollow stem, and a light plastic pot blows over on a patio. Black Knight Group and Blue Lace are the same tall class — they just need more height than a small bowl can hold upright.
Do Pacific Giants work in pots?
Not in a small or light pot. They need a heavy barrel and an early ring, or the ground. Compact Magic Fountain is the patio lead.
Summer Nights is a short Chinese spray, closer to a foot than a tower, so it suits a patio pot without lodging like a six-foot tower. Dwarf Larkspur is a woodland spring perennial — give it part shade and woodland soil, not a full-sun patio barrel.
Water, the empty saucer, and winter wet
Water when the top inch of mix is dry. Soak until water leaves the hole, then empty the saucer. Pots in full sun dry faster than beds, and they also rot faster if the tray never empties. [4] Feel an inch down before you flood a plant that wilted at noon — heat wilt on a drained pot is not always a cue to water again, but in a hot spell a 14-inch pot can need a soak every day.
How often do I water a potted delphinium?
When the top inch of mix is dry. Soak, then empty the saucer. Heat and wind on a patio may mean every day in peak summer.
Before hard freezes, move the pot to the sheltered side of a wall or an unheated garage so winter rain does not sit in the mix. Roots in a pot have less insulation than roots in the ground, and a mix that freezes wet kills the crown. Leave the saucer empty in January.
Can the pot stay out all winter?
Yes if it drains and sits out of standing rain. Move it to a sheltered wall or an unheated garage so the mix does not freeze wet.
Grow, stake, or cut spent spikes
Once the pot drains, How to Grow Delphiniums covers slugs, toxicity, and the same rich moist soil if you are also planting in a bed. A tall stem still needs an early ring, and a spent spike still gets cut to the ground.
The first patio spike is often shorter than the same type in a bed — that is the pot, not a failed plant.
FAQ
Can I use garden soil in the pot?
No. It packs, stays wet, and brings weeds. Use bagged potting mix plus grit or perlite.
How many plants in one 14-inch pot?
One. A wider trough can hold two if air still moves between them and the pot stays heavy.
Do terracotta pots work?
Yes. They dry faster, which helps in a wet spell. You will water more often in heat.
Do I fertilize potted delphiniums every week?
No. A light potash feed once they are growing is enough. Heavy nitrogen makes soft stems that snap.
Do hanging baskets work?
No. They are too shallow and too light for a spike. Use a 12–16 inch pot. Annual larkspur in a basket is a different plant.
Do I still need to stake a potted plant?
Compact types often need only a low ring. Tall Pacific types still need an early brace — see Staking Delphiniums.
Is annual larkspur the same pot plant?
No. Annual Consolida is a different plant with a different life cycle. Confirm the Latin. See Types of Delphiniums.
Can woodland dwarf larkspur live in a patio pot?
It is a spring woodland perennial, not a Magic Fountain patio plant. Give it part shade and a drained pot, or a woodland bed.
When do I empty the pot at season end?
After frost blackens the tops, cut the spent stems and keep the crown in its pot if you will overwinter it cold and dry. A dead wet crown is compost.
Can I mix thirsty annuals in the same tub?
No. Those partners force extra water on the crown. Grow one delphinium per pot, or pair it with plants that like the same wet-dry cycle.
Related guides
Recommended plants
References
- [1] NC State Extension Plant Toolbox -
https://plants.ces.ncsu.edu/plants/delphinium-elatum/ - [2] Royal Horticultural Society -
https://www.rhs.org.uk/plants/delphinium/perennial/growing-guide - [3] Epic Gardening -
https://www.epicgardening.com/delphiniums-pots-containers/ - [4] Horticulture.co.uk -
https://horticulture.co.uk/blogs/growing/delphinium-in-pots
This note is part of Delphinium Guides.
More container notes by plant live in Container Growing Guides.
Updated: Reviewed by Bosquelle Editors