Growli

Troubleshooting

'Walla Walla' Onion problems — and how to fix them

'Walla Walla' Onion (Allium cepa 'Walla Walla') is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.

Bolting (premature flowering)

Overwintered plants that experience prolonged cold or a stress check run to seed, producing a woody central stalk and poor bulbs. Sow at the right time and choose recommended sowing windows.

Poor storage / rot

Sweet, high-moisture, thin-skinned bulbs keep only a few weeks. Cure thoroughly in a dry, airy place and use promptly; they are not a long-keeping onion.

Onion white rot

Soil-borne fungus causing yellowing tops, fluffy white mycelium, and rotting bulb bases. It persists for years, so practise long rotations and never plant into known-infected ground.

Onion fly / thrips

Onion fly maggots tunnel into bulbs while thrips silver the foliage and check growth. Use insect mesh against onion fly and keep plants well-watered to limit thrips damage in hot spells.

Prevent 'walla walla' onion problems before they start

Most 'walla walla' onion issues are care-mismatch, not bad luck. Dial in the basics:

Looking for 'walla walla' onion in general rather than its problems? Read the full 'walla walla' onion care guide — light, water, soil and feeding.

'Walla Walla' Onion problems — FAQ

Why is my 'walla walla' onion bolting (premature flowering)?

Overwintered plants that experience prolonged cold or a stress check run to seed, producing a woody central stalk and poor bulbs. Sow at the right time and choose recommended sowing windows.

Why is my 'walla walla' onion poor storage / rot?

Sweet, high-moisture, thin-skinned bulbs keep only a few weeks. Cure thoroughly in a dry, airy place and use promptly; they are not a long-keeping onion.

Why is my 'walla walla' onion onion white rot?

Soil-borne fungus causing yellowing tops, fluffy white mycelium, and rotting bulb bases. It persists for years, so practise long rotations and never plant into known-infected ground.

Why is my 'walla walla' onion onion fly / thrips?

Onion fly maggots tunnel into bulbs while thrips silver the foliage and check growth. Use insect mesh against onion fly and keep plants well-watered to limit thrips damage in hot spells.