Why aren't my garlic and onions producing big bulbs?

I had someone recently come up to me at an event and tell me their onions never grew very big bulbs. Upon asking a simple question, the answer was very clear. Garlic, onions, shallots, chives, leeks and scallions are in a family called Allium. Basically the onion & garlic family. They grow similarly and when let "go to seed" they will all produce what is called a "Scape" and ultimately a bulb of flowers that can contain seeds. Whether or not those seeds are viable (meaning able to reproduce) is quite another thing.

I plant all of my onions, scallions and leeks from little black seeds, so I can replant the following season and share the many seeds with others. As your young plant is growing, it will eventually have a tender center stalk called a "Scape." This is where the potential reproduction begins.

When the young plant grows to about a foot or so high, keep a watch out for a center stalk that is tender and looks like the photo above. Once these scapes arch and begin to curl, you will want to cut them off as low to the ground as possible. DO NOT THROW THEM AWAY! Scapes are very edible. You can cut up the tender green stalk, you can roast them and even open up the pod to retrieve mini cloves. They maintain that delicious garlic flavor. Some people will even grill or roast them.

The reason for cutting them off once they curl, is because the plant is using all of it's energy and nutrients to put into the bulb for potential reproduction, and doesn't give much energy to the bulb growing underground. If you leave a scape on, when it's time to harvest, you will have a very small bulb. The only reason to let the scape continue to grow, is if you want to try to produce viable seeds. As the scape grows, it will ultimately open up and you'll have both small flowers and what are called bulbils (tiny cloves). So, if you want larger bulbs growing, make sure you cut those off as soon as the scape begins to curl. If you want to try for seeds, that's another process. The bulbis are the little purple pods and if you gently remove those and leave the flowers, they will ultimately produce the tiny black true seeds. But wait! There's more you need to know!

Because most garlic is grown from separating the cloves from the bulbs and planting each clove (which is easier and less time consuming) for generations, the plants themselves have become more sterile over the generations. Can you plant new garlic from the bulbils and seeds? Yes, but.... you're looking at a minimum of a couple years to get them to produce the bulbs we're using to buying or growing. However, the good news is, if you're willing to take a couple years to let them grow and replant, and allow the flower parts to pollinate with other garlic plants, then with each year you will get more and more viable seeds you can plant and literally continue the process with your own seeds. The first year you may only get "some seeds" but with each planting season, if you keep the process going, by the 3rd year you should be very successful in not only growing, but harvesting your own viable seeds.

I start my leeks and onions from seed each year, that is because I save the seeds. When you let the flowers grow fully, each bud will contain a small black seed. Plant those seeds one season. Then harvest the bulbis and or the seeds to directly sow into the ground. It may take the 2nd year for a full harvest, but you will have a ton of viable seeds of your own and increase the size of your harvest!

Each bud will contain a small black seed.