How to preserve zucchini seeds

In this brief guide, we are going to answer the question “how to preserve zucchini seeds.”

How to preserve zucchini seeds 

Zucchinis seeds must be harvested, cleaned and dried for preservation. After drying they can be stored in ziplock bags or airtight containers until needed.

Zucchinis are easy to grow, summertime vegetables. Zucchini seeds can be harvested from fully ripe zucchinis and stored for planting. If harvested and stored properly, zucchini seeds may be viable for up to 8 years.

One mature zucchini holds about 500 seeds, so a single mature zucchini is all you need to harvest enough and more seeds for the next year’s crop. The physiological maturity characterizes the stage where seeds reach their maximum dry matter, germination and vigor values. Harvesting at this stage avoids obtaining unripe and drying-intolerant seeds, as well as the exposure of seeds on the field to biotic and abiotic factors that reduce their quality (1).

For the legume cluster per se, the local markets were the most important source, by far: 45.9% of seed transactions (so almost a half of all sources combined) (2).

How to harvest and clean zucchini seeds for preservation

Always choose a completely ripe and mature zucchini for harvesting seeds. 

Edible zucchinis are immature and their seeds have not developed completely. A completely mature zucchini would be large, with a very tough outer skin and it is certainly inedible.

To harvest and clean zucchini seeds (4):

  • Cut open a fully mature zucchini. The zucchini would be very hard and a kitchen knife may not cut through. If so, use an axe or hammer. 
  • Scoop out the seeds using a spoon or from your hands. 
  • Separate the seeds from the pulp and fibres and transfer the seeds into a clean container. The leftover pulp and fibres can be used to make compost or as bird feed.
  • Clean the zucchini seeds. The seeds can be cleaned by washing with a little bit of dish soap and water or by fermenting them in water
  • To wash the seeds in dish soap and water, immerse the zucchini seeds in a mixture of dish soap and water for a couple of hours and then wash them with clean water.
  • If you prefer fermenting, place the zucchini seeds in water for a couple of days. Simply add some water to the zucchini seeds and leave them in a warm place for a couple of days. This would make the zucchini seeds completely clean.
  • After the seeds have fermented, add more water to the zucchini seeds. This would make the viable seeds sink to the bottom and the dead seeds and remaining pulp will float to the top.
  • Drain the excess water and the dead seeds and pulp.
  • Clean the seeds again to remove the final traces of pulp and fibres.
  • Pat try the seeds using paper towels.

Now you can dry the seeds using one of the methods discussed next.

How to dry zucchini seeds 

Zucchini seeds must be dried before storage. Drying removes moisture from the zucchini seeds that may cause the growth of bacteria and mould. When completely dried, the zucchini seeds would be crips and not bendable.

A 10-year storage life can be achieved by drying seed to less than 8 percent moisture. To do so, dry seed at 100 degrees F for six hours. Obtain this temperature by spreading the seed out in direct sunlight. However, because sunlight is harsh and easily can exceed this temperature, drying in the shade is better.Never use a microwave oven. You may use a conventional oven if you keep the door open and the seed is not heated to more than 100 degrees. Package the seed in moisture-proof containers and store it in a refriger-ator or deep freezer (3).

Zucchini seeds can be dried in one of the following 3 ways.

  • Air drying: Simply spread out the zucchini seeds on a clean tray and place them in a warm room. It would take about 2 to 3 days for the seeds to dry completely. Observe the seeds regularly to make sure there is no mould growth.
  • Using an oven: Zucchini seeds can be dried by placing them in an oven. Take note that you should not turn on the oven temperature. Simply turn on the oven light and place the tray with the seeds inside. The heat from the light would dry the zucchini seeds in about 48 hours.
  • Using a food dehydrator: Zucchini seeds can be dehydrated using a food dehydrator at 95 degrees Fahrenheit or the lowest possible temperature setting of the dehydrator. Make sure that the temperature does not rise above 100 degrees as it may damage the seeds. 

How to store zucchini seeds

Vegetable seeds can last for several years if you store them properly. Seeds should be stored in a cool, dry, dark place. Moisture, heat and light can cause seeds to sprout or rot (4). 

Dried zucchini seeds can be safely stored for about 8 years. Transfer the dried seeds into ziplock bags or airtight containers and store them in a cool dark place until you are ready to use them. Make sure that the ziplock bags or airtight containers are labeled so that they are not confused with other seeds.

How to use preserved zucchini seeds

Zucchini seeds do store well. However, they might not be viable after a few years. So it is a good idea to check if the stored zucchini seeds are still viable before planting them. A water test can determine the viability of zucchini seeds

To check if zucchini seeds are viable :

  • Put the zucchini seeds into a container filled with water.
  • Allow the seeds to sit for about 15 minutes.
  • After 15 minutes, the variable seeds would sink to the bottom. The seeds floating on the top are not viable and they would not sprout if planted.


In this brief guide, we answered the question “how to preserve zucchini seeds” and discussed the method to harvest, clean, dry and store zucchini seeds. We also discussed how to check the viability of zucchini seeds.

If you have any questions or comments, please let us know.


  1. Silva, Hellismar Wakson da, et al. Physiological maturity and drying speed in the quality of zucchini (Cucurbita pepo L.) seeds. J Seed Sci, 2017, 39, 142-149.
  2. Sperling, Louise, et al. Tailoring legume seed markets for smallholder farmers in Africa. Int J Agri Sustainab, 2021, 19, 71-90.
  3. Ells, James E., Louis N. Bass, and D. Whiting. Storing vegetable and flower seeds. Colorado State University Cooperative Extension, 2003.
  4. Zucchini. University of Saskatchewan.