Propagating Currants and Gooseberries by Stem Cuttings and Layering
by Patricia Holloway and Lacey Higham
Currants and Gooseberries in »¨½·Ö±²¥
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Both wild and cultivated currants and gooseberries grow in »¨½·Ö±²¥â€™s gardens. The wild red currant, Ribes triste, adapts well to gardens and can be grown as an individual plant or a low hedge. Other wild species of Ribes include many that are edible, but not necessarily palatable. Some have fruits, foliage and/or stems covered with glandular hairs or prickles. Others have an objectionable odor: The northern black currant is harvested from wild stands and is grown in gardens. The Canadian gooseberry was introduced to »¨½·Ö±²¥ gardens from the Whitehorse, Yukon region. It has small, but abundant fruit. All wild currants and gooseberries have medicinal properties, and have been used for centuries by northern indigenous people. They also attract birds, small mammals and other wildlife to gardens. Most cultivated red and white currants belong to the species, Ribes sativum, while Black currants are mostly Ribes nigrum. North American gooseberries are Ribes grossularia and hybrids. Europan gooseberries include R. uva-crispa. Breeders have incorporated more than 20 species and hybrids of Ribe into cultivars (cultivated varieties). They originate mostly from Europe and North America. More than a dozen cultivars are hardy in »¨½·Ö±²¥. Check with your local Cooperative Extension office for a list appropriate for your region. |
Ribes hudsonianum — northern black currant |
Ribes laxiflorum — trailing black currant (blue-black bristly/hairy fruit)
Ribes triste — northern red currant
R. oxyacanthoides — Canadian gooseberry (red, green, purple, and/or black fruit)
Ribes bracteosum — Stink currant (dark blue fruit with whitish bloom)
Ribes lacustre — Prickly swamp currant
Ribes glandulosum — Skunk currant (red bristly/glandular fruit)
Propagation by Stem Cuttings
Red, black and white currants are some of the easiest fruit crops to propagate by stem cuttings. Gooseberries root from stem cuttings, but it can take longer. Some cultivars are notoriously slow to root, and gloves are a must to avoid the numerous thorns. Easy-to-root cultivars usually begin showing roots in 2 to 3 weeks, and cuttings from containers can be potted up or planted in about 8 weeks, depending on growing conditions and the cultivar (cultivated variety).
Spring Hardwood Cuttings
Spring hardwood cuttings consist of branch tips with one-year-old wood that has not yet broken bud. Plants are not dormant, so bud break will be rapid. Cut stems into pieces that have a minimum of four buds per stick (5 to 8 inches in length). The bottom cut should be just below a bud and treated or untreated with hormones. Insert into sterile potting mix so that at least half of the buds are buried in the mix. Cover container with clear plastic tents or bags to reduce drying, and place in a warm and sunny location.
Rooting usually occurs by mid-summer, and rooted cuttings may be transplanted outdoors. If rooting is slow, they may also be left in the container, moved indoors to cold storage (33 – 40o F; 0.5 – 4.4o C) or mulched heavily (including all sides of the container) with wood chips or compost, then left outdoors at the end of summer. Snow cover with mulch is critical to survival.
Softwood Cuttings
Cuttings taken in mid-summer from actively growing shoots require special handling because they can wilt and dry out rapidly. Collect the cuttings into buckets of water so they do not wilt. Remove half the leaves or consider cutting the large leaves in half widthwise to reduce water loss. Cuttings may be very short. Some commercial growers make leaf-bud cuttings using a single leaf and a single bud. Cuttings might be 2 inches long at most. Others use the entire shoot tip which may be 3 to 5 inches long.
Treat with a low-dose rooting hormone designed for softwood cuttings, and stick immediately into potting mix or a 1:1 mix of horticultural grade vermiculite:perlite. The exact mix needs experimentation because success depends on moisture levels, amount of shade, and air temperature.
Softwood cuttings can be the fastest, most successful method of propagation, but it takes time to get conditions just right. Take cuttings a few days too early or late, and the cuttings rot. Propagators learn what the cuttings look like, the maturity, color, and length of the stem to have success. These types of cuttings must never dry out. Commercial growers use greenhouse benches that are bathed in mist or fog to get good rooting. Homeowners can make a humidity chamber out of plastic tents and humidifiers or foggers – anything to keep cuttings turgid until rooting. Rooted leafy cuttings must be hardened off just like flower and vegetable transplants before they are planted outdoors.
Ripewood Cuttings
Cuttings of new growth taken in late summer/ autumn are made and treated the same as spring hardwood cuttings. They may have leaves on them, but plant dormancy has begun, and leaves usually begin to yellow and fall off shortly after making the cuttings. If taken in early August, cuttings may root before the season ends, but they are too tender to endure planting outdoors in Interior »¨½·Ö±²¥. Locations with a longer growing season (South Central, coastal areas) will survive planting outdoors as long as the cuttings are well rooted with secondary branching.
Winter Hardwood Cuttings
Collect tip cuttings of one-year-old wood in late autumn or early winter when plants are dormant. They may still have leaves attached that should be pulled off. Make 6- to 8-inch cuttings similar to spring hardwood cuttings. Treat with a rooting hormone. Instead of planting, bundle in sets of 12+ cuttings. Tie with string, flagging or a rubber band. Label the bundles. Use a plastic container — a shoebox or storage container — and layer about 2 to 3 inches of barely moistened vermiculite on the bottom. Lay the bundles on their side in the boxes, and completely cover with more vermiculite. Close the lid to avoid moisture
loss. Store cold (33 – 40°F; 0.5 – 4.4°C) in refrigerator or other cold storage until spring. Do not allow to freeze or dry out. In spring, remove the bundles, and plant individual cuttings outdoors (weather and soils permitting) or in containers. Treat the same as spring hardwood cuttings.
Cuttings in Water
Softwood and ripewood cuttings may be stuck in jars of water and will begin to root in three to four weeks. Success is not as great as planting in potting mix, but it is an easy method for home gardeners. Take 4- to 6-inch cuttings of new growth with leaves. Remove leaves from lower portion of the stems so they are not submerged. Place immediately into jars of water that have been covered with foil to exclude light. Place in a warm, sunny window or greenhouse. Check cuttings often and remove from water when well rooted. They need to be planted in potting mix for at least one month before being planted outdoors. This allows the roots to acclimate from a water environment to soil.
Direct Stick Cuttings Outdoors
Depending on weather conditions, stored cuttings (see winter hardwood section) and spring hardwood cuttings may be directly stuck into well-composted, silt loam or sandy loam garden soils in spring as soon as soils warm up. This method is not as successful with gooseberries as with currants. Sticking cuttings through clear or IRT (infrared transmitting) plastic that keeps soils moist and relatively warm can be faster.
Use pre-treated, stored winter hardwood cuttings or take 5- to 8-inch cuttings (minimum three buds) of one-year-old growth (shoot tips) in spring just before new growth begins. Make the bottom cut just below a bud. Optional — treat cuttings with rooting powder or quick-dip solution of IBA (Indole-Butyric acid), e.g., Rootone®, Hormodin®, Dip-NGrow®. The rooting hormone is not necessary, but it can hasten rooting and make it more uniform. Stick cuttings so that at least half of the buds are buried in the soil. Leave in place for the summer. If successful, new leafy growth will begin. To avoid storing cuttings over winter, leave them in place in the garden and transplant them the following spring.
Propagation in Containers
Cuttings may be taken in spring before growth begins (spring hardwood), summer (leafy softwood), late
summer/autumn (ripewood) or early winter (winter hardwood).
Best containers for propagation are clean, washed, sterile (dip in 10% Clorox® for 30 minutes, then rinse), deep containers. Traditional cell packs will work, but deeper containers allow for more of the cutting to be buried. Good choices are 2-inch cells that are 4 to 6 inches deep filled with sterile peat-lite potting mix (e.g., Sunshine® or ProMix®.) Moisten the mix and allow it to drain. Containers used for tree seedlings (e.g., Spen-cer-Lemaire Rootrainers®, Hillson®) are also excellent.
Propagation by Layering
Layering is a method of rooting that takes place while the stems are still attached to the main plant. Many currant and gooseberry plants have floppy stems that naturally grow toward the ground. These stems often get covered with leaf litter and soil and form roots on the buried portion of the stems. If you don’t annually prune bushes to maintain upright shoots, layering can be quite common and a way to get a few more plants. Layering does not produce hundreds of plants like cuttings, but it is a very successful method.
Gardeners often help nature by bending branches to the ground, securing the branches with a peg, rock or board, then waiting a full season for roots to appear. The easiest method is called simple or tip layering. The branch is bent to the ground, then the tip is forced upward using a peg. Alternatively, the branch can lie on the ground as long as the growing tip is exposed. The tip becomes the aerial growing point for the new plant.
Simple layering is usually started in spring or early summer. Wherever the branch touches the ground, some people will scrape away the bark and dust the wound with rooting hormone to speed up the process. It is not necessary. Layering can be as easy as placing a rock on a branch so it stays in contact with the soil.
The layer is often kept in place until the following season, then cut from the main plant and re-planted. Rooting may be rapid enough to cut from the main plant later in the first season. However, the new plant must be re-planted right away, potted up, or stored over winter. Most people just wait until the next season.
Propagation by Seeds
Currants and gooseberries have fleshy fruit called a berry, each containing multiple seeds. Extract the seeds by mashing the fruits against a metal screen or placing berries in a blender with water (about 3:1 water to berries by volume). Pulse the berries/water until the seeds separate from the pulp. Good seeds will sink to the bottom of the blender. Pulp and empty seeds will float. Pour off the pulp and air dry seeds on a paper towel.
Seeds of most black currants sown immediately after extraction often germinate in 2 to 3 weeks. Sow in a sterile potting mix, keep moist, and provide 14 – 20 hr of light and alternating day/night temperatures (86–75oF [30–24oC]). Seeds may also be sown outdoors in autumn, allowed to overwinter in well-composted garden soils or in shallow flats or containers. Keep the seeds watered until freeze-up, then mulch with leaves. The main problem with direct seeding is predation by small mammals.
Indoors, seeds/fruits may be stored frozen for five years or more. Dried seeds extracted from the fruit must be cold stratifiedbefore sowing. Cold stratification involves mixing seeds in sealable plastic bags with slightly moist sand (3:1 sand:seeds by volume). Hold in the refrigerator (NOT the freezer) 40oF (4oC) for 3 to 4 months. Separate the seeds from sand and sowimmediately onto a sterile potting mix without allowing the seeds to dry out.
Seeds may also be sown directly into containers on top of moistened potting mix and very lightly covered with vermiculite. Cold stratify by enclosing containers in plastic bags. Refrigerate containers at 40oF (4oC) for 3 to 4 months. Watch them carefully. Seeds may begin to germinate in the refrigerator.
Remove pots/seeds from the refrigerator. Place under lights (16 –18hr) in alternating temperatures (86–75oF [30 –24oC] with high temp during light cycle). Germination might have already started in the refrigerator. Otherwise, seedlings should appear within 2 to 3 weeks.