June Is Strawberry Season

For generations, early summer has meant preserving the harvest so as not to go hungry during the winter months. Nowadays, preserving is no longer a household necessity to carry us through the rest of the year, but for many, it is still an enjoyable activity. Jams are the best when made from fresh fruit. Even brief refrigeration can shift and change the pectin properties, and pectin is the magician when it comes to the jellying process. Strawberry season in our region is about three weeks, so plan well and get ready! According to the Environmental Working group, year after year, strawberries top the Dirty Dozen list as being treated with the most fungicides and pesticides, so they recommend purchasing organic strawberries for health reasons. There are also U Pick farms in our area, but only a few practice pesticide-free growing. You can also purchase organic strawberries from the farmers’ market, but be prepared to get up early and stand in a long line. You can learn more about shopping at the farmers’ markets here

fresh strawberries with leaves on

Already the Romans…

You can learn more about strawberries, the only fruit with their seeds on the outside, their nutritional value, and their culinary history; check here.                      

Pectin is the magician of preserving

Jam is only as good as the fruit you are using. Unripened fruit is less flavorful but contains more pectin. For the best outcome, combine slightly underripe and just ripe fruit. For the jam to reach the jelly stage during cooking, it must contain pectin, which is a natural carbohydrate that is concentrated in the skin and seeds of the fruit. Apples and citrus fruits are highest in pectin and are used as the base for many packaged pectin powders. Cook jam gently and do not overcook it, as it may “kill” the pectin. Also, the shorter the cooking time, the better the flavor. The right balance of sweetness and acid is required in jam making and is achieved by adding a measured amount of lemon juice or citric acid. 

rows of picked strawberries in pint baskets

jars of strawberry jam sitting on counter

Strawberry Jam

Magda Born
The best jams are made from small batches of strawberries. If your first attempt does not turn out well, keep notes on what you did and practice more next time. Hull and slice strawberries before weighing. Most recipes use an equal amount of sugar for fruit since sugar is both a thickener and a preserving agent.  
It is best to use strawberries that have not been refrigerated since refrigeration can lower the pectin in the fruit. Frozen strawberries are not suitable for canning. 


  • 2 lb About 8 cups of fresh strawberries
  • 2 lb Granulated sugar
  • ½ cup Lemon juice
  • 1 Tbs Sherry or Kirsch optional


  • Start with a small batch.Small batches cook faster, so you will preserve the fresh flavor. Wash and hull strawberries and cut them into quarters of about equal sizes for even cooking.
    fresh cut up strawberries and lemons on a cutting block
  • Toss the berries in a non-reactive pot or Dutch oven. Add lemon juice (I even add the remains of the lemon) and sugar. Mix well and let sit, covered for up to 8 hours at room temperature to let them marinade and release their juices.
    strawberries and lemons sitting in a bowl with juice and a wooden spoon stirring
  • While the strawberries are marinating, wash your jars with hot water and soap our jars, and boil them for a few minutes in a water bath. Place them on a clean kitchen towel to dry and cool.
    jars sterilizing in boiling water
  • Cook fruits in a wide, shallow non-reactive pan. Cook over medium-high. Strawberries need to be cooked evenly to extrude pectin but not so long as to kill it, which would make the preserves too runny. Stir occasionally to avoid scorching. When the jam is done, remove the lemon and stir in the Sherry or Kirsch.
    strawberries cooking in a pot
  • Ladle the jam carefully into clean jars. They can be stored in the refrigerator for up to three months. If you want to store them longer, they need to be processed in a canner while submerged under 2 inches of water, processing them for 10 minutes. Let the jar cool upside down for proper sealing. If a seal fails, reprocess or refrigerate it and use it within three months.
    filled jars processing in boiling water
  • The jars are cooled upside down to make sure they seal properly. Store fruit spreads in a cooler, dark place, such as a basement. Exposure to heat or sunlight can cause fruit spreads to lose their color, flavor, and texture. When cooked correctly, the resulting jam has an intense strawberry flavor with vibrant red color.
    cooling jars sitting upside down on counter


foolproof preserving book cover

Foolproof preserving: a guide to small batch jams, jellies, pickles, condiments, and more by the editors at America’s Test Kitchen. 

Call Number 641.42 FOOLPROO

preserving with pomonas pectin book cover

Preserving with Pomona’s pectin: the revolutionary low-sugar, high-flavor method for crafting and canning jams, jellies, conserves, and more by Allison Carroll Duffy and the partners at Pomona’s Universal Pectin. 

Call Number 641.42 DUFFY

jam session book cover

Jam session: a fruit-preserving handbook by Joyce EserskyGoldstein and Ed Anderson, Ed

Book Call Number: 641.564 GOLDSTEI

jam on book cover

Jam on: the craft of canning fruit  by Laena McCarthy

Call Number 641.42 MCCARTHY

175 best jams jellies marmalades book cover

175 best jams, jellies, marmalades & other soft spreads by Linda J. Amendt

Call Number 641.852 AMENDT

perfect preserves book cover

Perfect preserves: how to make the best jams and jellies ever by Maggie Mayhew

Call Number 641.852 MAYHEW

Magda Born


Community Services Librarian

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625 Minnesota Ave.

Kansas City, KS 66101

913-295-8250 ext 1103