By Allison Carroll

I love rhubarb season. Here in Maine, where I live with my family in an old farmhouse on a few acres, rhubarb is one of the earliest fresh green edibles to emerge from the soil each spring, so it’s always a much-anticipated treat. It’s delicious in pie, in jam, or simply stewed with a little honey.

Rhubarb’s sour, slightly astringent tang makes it a perfect partner for sweeter fruits. The combination of blueberries and rhubarb is less common than the typical strawberry-rhubarb pairing, but it really shouldn’t be. I adapted the Blubarb Jam recipe from one by jam-maker Kirsten Jennings, who first tried it at a local restaurant and liked it so much that she figured out how to make it at home herself.

About Rhubarb

Be sure to select fresh, firm stalks of rhubarb. If you’re harvesting it yourself, trim it thoroughly, completely removing and discarding all leaves. If purchasing at a farmers market or grocery store, it has already been trimmed. Always, the stalks are the only part you want to use as the leaves themselves are poisonous. (Ed. note: They are poisonous to livestock, too.)

Typically, rhubarb stalks are similar in size to celery stalks, though this can vary. The color varies also, from green to red and anywhere in between. For the deepest red jam, select stalks that are red rather than green. In terms of taste and texture, though, both work equally well—and both make delicious jam.

Preserving with Pomona’s Pectin by Allison Carroll Duffy (Fair Winds Press 2013) contains 75 inspiring recipes for low-sugar jams, jellies, preserves, conserves, and marmalades. It is available in bookstores and online.

Recipes

Blubarb Jam

Excerpted from Preserving with Pomona’s Pectin by Allison Carroll Duffy

Blubarb Jam is a low-sugar cooked jam made with Pomona’s Pectin. It is a lovely, deep blue color and a delicious, tangy treat.

Before You Begin:
Prepare calcium water. To do this, combine ½ teaspoon calcium powder (in the small packet in your box of Pomona’s Pectin) with ½ cup water in a small, clear jar with a lid. Shake well. Extra calcium water may be stored in the refrigerator for future use.

Yield: 4 to 5 cups

Ingredients
1 pound blueberries
1 pound trimmed rhubarb stalks
½ cup water
¼ cup lemon juice
2 teaspoons calcium water
1¼ cups sugar
2½ teaspoons Pomona’s
Pectin powder

Directions
1. Wash your jars, lids, and bands. Place jars in canner, fill canner 2/3 full with water, bring canner to a rolling boil, and boil jars for 10 minutes to sterilize them. (Add 1 extra minute of sterilizing time for every 1,000 feet above sea level.) Reduce heat and allow jars to remain in hot canner water until ready to use. Place lids in water in a small saucepan, heat to a low simmer, and hold until ready to use.
2. Rinse blueberries, remove stems, and mash in a large bowl. Set aside.
3. Rinse rhubarb, slice stalks lengthwise into thin strips, and then dice. Combine diced rhubarb in a saucepan with the ½ cup of water. Bring to a boil over high heat, reduce heat, and then simmer, covered, for 5 minutes, or until rhubarb is soft, stirring occasionally. Remove from heat and mash rhubarb.
4. Measure out 2 cups of the mashed blueberries and 2 cups of the mashed rhubarb (saving any extra for another use), and combine the measured quantities in a saucepan. Add lemon juice and the calcium water, and
mix well.
5. In a separate bowl, combine sugar and pectin powder. Mix thoroughly and set aside.
6. Bring fruit mixture to a full boil over high heat. Slowly add pectin/sugar mixture, stirring constantly. Continue to stir vigorously for 1 to 2 minutes to dissolve pectin while the jam comes back up to a boil. Once the jam returns to a full boil, remove it from
the heat.
7. Can Your Jam: Remove jars from canner and ladle jam into hot jars, leaving ¼ inch of headspace. Remove trapped air bubbles, wipe rims with a damp cloth, put on lids and screw bands, and tighten to fingertip tight. Lower filled jars into canner, ensuring jars are not touching each other and are covered with at least 1 to 2 inches of water. Place lid on canner, return to a rolling boil, and process for 10 minutes. (Add 1 extra minute of processing time for every 1,000 feet above sea level.) Turn off heat and allow canner to sit untouched for 5 minutes, then remove jars and allow to cool undisturbed for 12 to 24 hours. Confirm that jars have sealed, then store properly. Eat within 1 year. Lasts 3 weeks once opened.

Frozen Ease!
You can substitute frozen berries for the fresh, and if you don’t have a lot of time, this is a good option. Simply defrost the berries, and then mash them as the recipe calls for. After defrosting, the berries will be in a lot of juice, but don’t drain them—simply incorporate all of the juice into the mashed berries.

Strawberry-Rhubarb Jam

Strawberry-Rhubarb Jam is a low-sugar or low-honey cooked jam made with Pomona’s Pectin. It is an early summer classic—nice combination of tart and sweet. Feel free to use other sweeteners that measure like sugar in this recipe. For example, you can use a stevia product that measures like sugar. You can also use agave instead of honey. You can find this recipe and many other low-sweetener jam and jelly recipes on the Pomona’s Pectin website (pomonapectin.com).

Before You Begin:
Prepare calcium water. To do this, combine ½ teaspoon calcium powder (in the small packet in your box of Pomona’s Pectin) with ½ cup water in a small, clear jar with a lid. Shake well. Extra calcium water may be stored in the refrigerator for future use.

Yield: about 5 cups

Ingredients
2 cups mashed strawberries (about 4 cups whole strawberries)
2 cups cooked rhubarb (chop rhubarb, add a little water, cook until soft, measure)
2 teaspoons calcium water
2 tablespoons lemon juice
½ cup up to 1 cup honey or ¾ cup up to 2 cups sugar
2½ teaspoons Pomona’s
Pectin powder

Directions
1. Wash jars, lids, and bands.
Place jars in canner, fill canner 2/3 full with water, bring to a boil. Turn off heat, cover, and keep jars in hot canner water until ready to use. Place lids in water in a small saucepan; cover and heat to a low boil. Turn off heat and keep lids in hot water until ready to use.
2. Wash, remove hulls, and mash strawberries. Prepare rhubarb. Measure fruit into saucepan.
3. Add calcium water and lemon juice and mix well.
4. Measure sugar or room
temperature honey into a bowl. Thoroughly mix pectin powder into sweetener. Set aside.
5. Bring fruit mixture to a full boil. Add pectin-sweetener mixture, stirring vigorously for 1 to 2 minutes to dissolve the pectin while the jam comes back up to a boil. Once the
jam returns to a full boil, remove it from the heat.
6. Fill hot jars to ¼-inch of top. Wipe rims clean. Screw on two-piece lids. Put filled jars in boiling water to cover. Boil 10 minutes (add 1 minute more for every 1,000 feet above sea level). Remove from water. Let jars cool. Check seals; lids should be sucked down. Eat within 1 year. Lasts 3 weeks once opened.

Note: If you’re not sure your jam is sweet enough, taste it after the pectin is dissolved and jam has come back up to a boil. Not sweet enough? Add more sweetener and stir 1 minute at full boil.