When to Plant Welsh onion in Marion, IA

One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Marion you can determine when to plant welsh onion by referring to the USDA zone info.


Planting Calendar for Welsh onion

Frost tolerance for welsh onion: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Welsh onion tend to make it in some cold which means that you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant welsh onion
Possibly ok, but a risky time to plant welsh onion
Probably not a good time to plant welsh onion

The earliest that you can plant welsh onion in Marion is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant welsh onion and expect a good harvest is probably August. If you wait any later than that and your welsh onion may not have a chance to grow to maturity. If you are starting your welsh onion indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Marion the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Marion is not always accurate the actual date of last frost changes from year to year. Half of the time in Marion you get a frost after April 15 so be sure to be ready to cover your welsh onion if you have a surprise late frost.

USDA Zone Info for Marion

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Marion

You may be interested in your other planting guides for Marion.