Good shallot plant spacing means putting sets 3 to 8 inches apart in the row. How far apart to plant shallots depends on your goal. Tight spacing gives you small single bulbs. Wide spacing gives you big clusters with lots of offsets.
I ran a test in my raised beds last spring with three spacings in the same bed. The sets crammed in at 2 inches apart grew into single small bulbs with thin skins. The sets with 6 inches of room each made fat clusters of 8 to 12 bulbs per set. The crowded plants fought so hard for water that half came out tiny. I won't pack them in tight again after seeing the difference with my own eyes.
Data from Utah State University Extension backs up what I saw. Dense planting forces each set to make just one bulb. The roots compete for the same small patch of soil and nutrients. Wide spacing of 6 inches or more lets the plant divide into clusters of 10 to 15 bulbs from a single set. You plant fewer sets per bed with wide gaps. But your total harvest ends up much bigger when the season wraps up.
Shallot row spacing matters just as much as the gap between sets. Leave 12 to 18 inches (30 to 45 centimeters) between rows so you can fit a hoe in for weeding. Tight rows make weeding hard and block airflow around the leaves. Poor airflow leads to fungal problems that spread fast in damp weather. I keep my rows at 15 inches since this works well for both my weeding tools and air flow between the plants.
A 4 by 8 foot (1.2 by 2.4 meter) raised bed with 6-inch spacing holds around 48 sets in 4 rows. Each set can produce 10 to 15 bulbs at that spacing. That single bed gives you 480 to 720 bulbs from one planting. You get enough to cook with all winter and still save sets for next year.
Pick your spacing based on your plans for the harvest. Tight spacing of 2 to 3 inches works if you want to pull green tops for salads at 50 to 60 days after planting. Medium spacing of 4 to 5 inches gives you decent clusters for the kitchen. Go with 6 to 8 inches if your goal is to multiply your stock and build up a big supply of planting sets over time.
I learned the hard way that depth matters as much as spacing. Plant your sets about 1 inch deep with the pointed end facing up. Push the base into loose soil and press the dirt firm around it. Water the bed right away so soil settles tight around each bulb.
Good contact between soil and the bulb base gets roots growing fast from day one. Check back in a week and press down any sets that frost or rain pushed up. Exposed bases dry out fast and the set dies before it ever sends out roots.
A quick walk through your bed each week during the first month saves you from losing sets to this problem. Once the green tops hit 4 to 6 inches tall, the roots have a strong grip and you can stop worrying about shifting. From that point on, just keep up with your watering and weeding until harvest time comes around. Your spacing work pays off big when you pull those fat clusters out of the ground.
Read the full article: Growing Shallots: Key Tips for Success
