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Specialty Seeds

Harvesting alsike clover seed
Oregon clover harvest.


Oregon became a specialty seed producer around the 1930s and has been growing various types of specialty seeds ever since. Around 1970 seed production began to increase in Central Oregon with the cultivation of onions and carrots for seed. Recent technology and the push towards globalization has allowed Oregon specialty seeds to be exported to many different regions of the world. About 20% of Oregon grass seed alone is exported outside of the United States. Specialty seeds are grown in many different regions of the state such as central, western, and southern Oregon.

What are They?

Specialty crops are essentially horticulture crops that include “fruits and vegetables, tree nuts, dried fruits, horticulture and nursery crops (including floriculture)”. These different crops must have the purpose of being used for food, medicinal purposes, or aesthetic gratification. Specialty seed crops are within this category, but are grown with the intention of growing them to harvest their seeds.

Some common crops that are grown for seed in Oregon include:

  • Cabbage, onions, radish, turnips, carrots, pumpkins, flowers, squash, parsley, Swiss chard, herbs, grass, legumes, spinach, mustard, garlic, kale, sugar beets, medicinal plants etc.

Why is it important to Oregon

According to the United States Department of Agriculture, the value of “seeds, oilseeds and horticulture” exports was about $940,553,000 in 2017. This is the largest valued agricultural export for the state of Oregon. Grass in Oregon is a major contributor to the seed production and is even responsible for giving the Willamette Valley the nickname “grass seed capital of the world”. Oregon is also a massive producer of carrot seed with Jefferson County producing 85% of all United State’s hybrid carrot seed.

Seed Harvests

Many of the different specialty seed crops that are grown in Oregon are planted, cared for and harvested differently. Here are some of the major crops and the processes they undergo in order to provide seed.

Sugar Beet

For commercial production of sugar beet seed, male and female plants are planted in a field. once the beet plants are growing, weeds are removed so that there is not any cross pollination. Once the flowers are pollinated, usually by honeybees, the male plants are destroyed. Once the seeds are swathed, they are left in a field to dry for a couple of days. After they are dry, a combine goes through the field and collects the seeds. They are then transported to a facility where they are further cleaned so that they are ready for distribution.


There is about 1,500 grass seed farms across Oregon. The grasses that are grown for seed are typically perennial which means that they will grow for longer than two years. Before a field is planted the ground is prepared by loosening the soil and ridding it of any weeds. Grass is then planted in either the spring or fall depending on the variety type. Grass seed is put in fields with a planting drill, and sometimes carbon banded. Grass seed is usually harvested in late June or early July. A machine called a windrower cuts the grass when it is still green to prevent seed shattering, then lays it into rows. The grass is then left to dry for 5-10 days before being harvested with a combine. After the seed is harvested, it is loaded into trucks and sent to the seed cleaning warehouses.



Onions requires two full growing seasons in order to be mature enough for seed production. Onions are triggered to bolt when certain temperatures and light exposure is met. Onions have an umbel inflorescence, that blooms with small white flowers. Seeds are mature when they turn black in color and should be harvested once 10% of the seeds on each umbel are exposed. Harvesting for onions can be direct or indirect. Direct harvesting is when a combine harvests all of the umbels from a field at one time. Indirect harvest is when the umbels are hand harvested. After onion seeds are harvested they are then dried and threshed to separate the seeds from the umbel. After the onion seeds are separated they are then cleaned. 


The most common way that specialty seed crops are pollinated in Oregon are by bees. In Oregon there are about 80,000 managed honey bee colonies that are used to pollinate different crops, including seed, in Oregon. Honeybees are a huge part of production, because every seed crop needs to have its flowers pollinated in order for it to produce seeds.


Fun Facts


Oregon is number 1 in the United States for growing sugar beet seeds.


In order for onions to bolt they must be exposed to 45-55 degree weather for about a month.


Oregon produces seed ranging from vegetables, grass, cereals, and a couple of other groups.


Bees are used to pollinate many seed crops such as onions, parsley, and alfalfa.


Sometimes controlled burns are used to help increase seed production as well as decrease diseases and weeds.


Oregon generates about $1 billion in annual economic activity just for grass seed alone.

Related References







Celebrate Oregon Agriculture: Specialty Seeds


Sugarbeet: A controversial seed crop in Oregon’s Willamette Valley.