Garden Tempo

Texas, U.S. · outdoor planting

When to plant onions in Texas

For spring, set onion plants about 4–10 weeks before the local frost-free date or sow seed about 6–8 weeks before it. Fall seed is not recommended in Regions I–II; Texas A&M gives November 1 for Region III, December 1 for Region IV and December 15 for Region V.

Choose the Texas timing rule
Spring
Plants: 4–10 weeks before; seed: 6–8 weeks before
Based on your local frost-free date
Fall
Seed: 8–10 weeks before first freeze where supported
Based on your local first freeze
Start with
Choose seed or plants first
The material changes the schedule. Do not place sets, plants and seed under one date, and choose an onion type adapted to the region’s day length.

Spring and fall are different calculations

Start with your local frost date

Texas is too large for one planting day. Spring timing is measured from the local average frost-free date. Fall timing is measured backward from the local first freeze, then checked against the Texas A&M regional anchor when one is published.

Spring rule

Plants: 4–10 weeks before; seed: 6–8 weeks before

Use the frost-free date for your garden, not a statewide average.

Fall rule

Seed: 8–10 weeks before first freeze where supported

Count backward from the local first freeze and leave room for establishment.

Texas A&M gardening regions

Regional planning anchors

Texas A&M divides the state into five gardening regions. The dates below are planning anchors, not boundaries that follow county lines and not promises about one exact garden.

Region I

Fall seed: Not recommended

Northern Panhandle

Region II

Fall seed: Not recommended

West Texas and the High Plains

Region III

Fall seed: Nov 1

North, East and Central Texas

Region IV

Fall seed: Dec 1

South Texas

Region V

Fall seed: Dec 15

Lower Rio Grande Valley

Plant only when the crop is ready

The calendar is the first filter

A date can be inside the planning range and still be a poor planting day. Check the crop-specific conditions before committing seed or plants.

  • The planting material and onion type are identified.
  • The bed is loose, well drained and ready for shallow establishment.
  • A fall seed crop is supported for the selected Texas region.

Method changes timing

How to start onions

The material changes the schedule. Do not place sets, plants and seed under one date, and choose an onion type adapted to the region’s day length.

Choose seed or plants

Start with material because spring countbacks differ and fall plants do not inherit the fall-seed rule.

Confirm regional adaptation

Use an onion type suited to the region’s day length; timing cannot correct a mismatched type.

Plant shallowly

Prepare a fine bed and avoid burying the growing point too deeply.

When the simple answer breaks

Early and late decisions

A usable planting page needs an action when weather, region or maturity no longer fits the headline range.

Region I or II fall seed

Do not manufacture a date

The Texas A&M regional table marks this method not recommended; choose a supported season or ask county Extension.

Using transplants

Use the plant schedule

The fall-seed regional row does not automatically apply to purchased onion plants.

Why this answer is shaped this way

Onions are a method-first page

A generic “when to plant onions” answer hides the material decision. Texas A&M separates plants from seed, and the regional fall table rejects seed planting in two regions.