Main content

What causes onions to bolt? What do the team think about crocs at the bottom of pots? How should I go about pruning my lilac tree? Kathy Clugston and the panel have the answers.

What causes onions to bolt? What do the team think about using crocs at the bottom of pots? How should I go about pruning my lilac tree?

Kathy Clugston and a panel of esteemed gardening experts visit West Horsley, Surrey, to tackle common horticultural challenges and share practical solutions. Joining her are pest and disease specialist Pippa Greenwood, botanist James Wong, and award-winning garden designer Juliet Sargeant.

Later in the programme, Bob Flowerdew wraps up our Edible Essentials series with a fool proof guide to feeding and watering your crops - ensuring a rich and rewarding harvest.

Producer: Matthew Smith
Junior Producer: Rahnee Prescod
Executive Producer: Carly Maile

Plant List
Questions and timecodes are below. Where applicable, plant names have been provided.

Q 鈥 My Ficus Ginseng has lost most of its leaves, what am I doing wrong? (01鈥35鈥)

Q 鈥 What do the team think about using crocs at the bottom of pots? (06鈥41鈥)

Q 鈥撯奀an the panel suggest shrubs that will flower late spring, early summer and thrive in chalky soil? (10鈥57鈥)

Juliet Sargeant 鈥
Philadelphus, mock orange
Philadelphus 'Manteau d'Hermine' (d), mock orange 'Manteau d'Hermine'
Weigela All Summer Red ('Slingco 1'PBR) (All Summer Series), weigela [All Summer Red]
Weigela All Summer Peach ('Slingpink'PBR) (All Summer Series), weigela [All Summer Peach]
Ceanothus, californian lilac

Pippa Greenwood 鈥
Magnolia stellata, star magnolia
Mahonia, oregon grape
Syringa pubescens subsp. patula 'Miss Kim', lilac 'Miss Kim'
Deutzia 脳 rosea 'Carminea', deutzia 'Carminea'

James Wong 鈥
Pittosporum tobira, japanese pittosporum
Wisteria

Feature 鈥 Bob Flowerdew鈥檚 Edible Essential guide to watering and feeding crops (16鈥56)

Q 鈥 What causes onions to bolt? (21鈥19鈥)

Q 鈥 Can the panel advise on what I can plant on a north facing one-and-a-half-meter border adjacent my mixed hedge? (25鈥37鈥)

Juliet Sargeant 鈥
Euphorbia robbiae, mrs Robb's bonnet
Anemone hupehensis, japanese anemones

James Wong 鈥
Digitalis, foxglove
Primula vulgaris (Pr/Prim), primrose
Hyacinthoides non-scripta, bluebell
Hakonechloa, japanese forest grass
Ferns
Lillies

Pippa Greenwood 鈥
Hardy geraniums
Epimedium
Helleborus, hellebore

Q 鈥 How should I go about pruning my lilac tree? (31鈥48鈥)

Q 鈥 What plants would the panel take from your current gardens if you were moving to a much smaller garden with very poor soil and lots of builder鈥檚 rubble in it? (35鈥23鈥)

James Wong 鈥
Tree ferns

Juliet Sargeant 鈥
Iris germanica, bearded iris
Ficus carica (F), fig
Salvia 'Royal Bumble', sage 'Royal Bumble'
Salvia 'Hot Lips', sage 'Hot Lips'
Salvia, sage
Salvia 'Amistad'PBR, sage 'Amistad'
Erigeron karvinskianus, mexican fleabane

Pippa Greenwood 鈥
Aubrieta
Eryngium, sea holly

Available now

42 minutes

Featured

  • .

Plant List

Questions and timecodes are below. Where applicable, plant names have been provided.

Q 鈥 My Ficus Ginseng has lost most of its leaves, what am I doing wrong? (01鈥35鈥)

Q 鈥 What do the team think about using crocs at the bottom of pots? (06鈥41鈥)

Q 鈥撯奀an the panel suggest shrubs that will flower late spring, early summer and thrive in chalky soil? (10鈥57鈥)

Juliet Sargeant 鈥

Philadelphus, mock orange

Philadelphus听'Manteau d'Hermine' (d), mock orange 'Manteau d'Hermine'

Weigela听All Summer Red听('Slingco 1'PBR) (All Summer Series), weigela [All Summer Red]

Weigela听All Summer Peach听('Slingpink'PBR) (All Summer Series), weigela [All Summer Peach]

Ceanothus, californian lilac

Pippa Greenwood 鈥

Magnoliastellata, star magnolia

Mahonia, oregon grape

Syringapubescens听subsp.听patula听'Miss Kim', lilac 'Miss Kim'

Deutzia听脳听rosea听'Carminea', deutzia 'Carminea'

James Wong 鈥

Pittosporumtobira, japanese pittosporum

Wisteria

Feature 鈥 Bob Flowerdew鈥檚 Edible Essential guide to watering and feeding crops (16鈥56)

Q 鈥 What causes onions to bolt? (21鈥19鈥)

Q 鈥 Can the panel advise on what I can plant on a north facing one-and-a-half-meter border adjacent my mixed hedge? (25鈥37鈥)

Juliet Sargeant 鈥

Euphorbiarobbiae, mrs Robb's bonnet

Anemone hupehensis, japanese anemones

James Wong 鈥

Digitalis, foxglove

Primulavulgaris听(Pr/Prim), primrose

Hyacinthoidesnon-scripta, bluebell

Hakonechloa, japanese forest grass

Ferns

Lillies

Pippa Greenwood 鈥

Hardy geraniums

Epimedium

Helleborus, hellebore

Q 鈥 How should I go about pruning my lilac tree? (31鈥48鈥)

Q 鈥 What plants would the panel take from your current gardens if you were moving to a much smaller garden with very poor soil and lots of builder鈥檚 rubble in it? (35鈥23鈥)

James Wong 鈥

Tree ferns

Juliet Sargeant 鈥

Irisgermanica, bearded iris

Ficuscarica听(F), fig

Salvia听'Royal Bumble', sage 'Royal Bumble'

Salvia听'Hot Lips', sage 'Hot Lips'

Salvia, sage

Salvia听'Amistad'PBR, sage 'Amistad'

Erigeronkarvinskianus, mexican fleabane

Pippa Greenwood 鈥

Aubrieta

Eryngium, sea holly

Broadcasts

  • Fri 20 Jun 2025 15:00
  • Sun 22 Jun 2025 14:00

Six of GQT鈥檚 naughtiest gardening innuendos

When Gardeners' Question Time got mucky.

Podcast