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Elisabeth C. Miller Library

Keyword: Propagation

Propagating asparagus plants

I planted young asparagus plants a couple of springs ago. This past fall, one of the plants produced fruits (small red balls like I’ve seen on Asparagus sprengeri.) I looked in my Hartman and Kester, but it did not mention means of using asparagus seeds to make more plants. Can this be done? If I left them on the plant outside all winter, are they still viable?

According to Franklin Herm Fitz in A Gardener’s Guide to Propagating Food Plants, it is possible to grow asparagus from seed, but possibly not if the seeds have been out in freezing weather:

“Collect the red berries from two-year-old or older female plants, harvesting before the first frost. Crush the berries and separate the seeds by hand (the seeds are large, shiny, and black) or by immersing them in water. The pulp will float as the seeds sink. Dry the seeds for 2 to 3 weeks. In the spring grow the new plants in deep, loose soil. After one season transplant them to a permanent bed (…) in early spring before growth resumes or in the fall after growth has ceased.”

Alternatively, as you probably know, asparagus roots may be divided and replanted, with the knowledge that each smaller root will take a year to become established so that it can produce a good crop.

propagating sedums and succulents

I am learning how to propagate plants for my yard. I am now into Sedums and other succulents. I am trying to learn how to propagate Echeveria x hybrida “The Rose.” This one has me totally baffled. Can you help?

First, here is some general information. The propagation method you choose for Sedum depends on the habit of the plant, according to the American Horticultural Society’s Plant Propagation (edited by Alan Toogood; DK Publishing, 1999). Most species will root easily from cuttings in 1 to 6 weeks.

Tender species can be propagated from leaf cuttings. Take leaves off a stem. Place on damp newspaper in bright shade at 61 degrees F. Roots and plantlets should form in 3 to 4 weeks. You can also use stem cuttings by taking 2 to 3 inches from the tip of a stem and allowing the cutting to callus for a day. With hardier forms of Sedum, use 3/4 to 1 1/4 inch stem cuttings.

The book Echeveria Cultivars by Lorraine Schulz and Attila Kapitany (Schulz Publishing, 2005) offers directions on propagating from offsets, cuttings, cuttings from crests, head cuttings, leaf and stalk cuttings, and seed.

propagating tree peonies from seed

I have a tree peony that started as a seedling from a plant of a friend gave me 8-10 years ago. I would like to try to propagate mine from seed. From the little I’ve read, it seems this is a difficult process. Can you help me?

I believe you are correct that propagating tree peonies from seed may be a little challenging. It can be done, but home gardeners may find it easier to propagate by grafting, which is described by a link at the end of this answer.

The American Horticultural Society’s Plant Propagation, edited by Alan Toogood (DK Publishing, 1999) rates seed propagation of deciduous tree peonies as moderate in level of difficulty. Another thing to bear in mind is that it will take several years before you see flowers on your new plants. In [late] summer, you would sow fresh seeds in pots and “provide two periods of chilling, such as two cold winters, with warmth between. Seeds are doubly dormant (roots emerge in the first year and seed leaves in the second). Guard against mice: they love the seeds.”

Another description of propagating from seed may be found in Jekka McVicar’s book Seeds (Lyons Press, 2003):

This seed has a double dormancy, producing roots in its first year and
leaves in its second. It needs two cold periods, with warmth in between.

Collect ripe, fresh seeds in early autumn. Sow individually in pots,
using standard soil-less seed mix, either peat or peat substitute mixed
with coarse horticultural sand. Mix to a ratio of 1 part soil-less mix +
1 part sand. Cover with coarse grit, then place outside exposed to all
weathers. Visible germination occurs during the second spring. Grow on in
a cold frame for 2 years before planting out.

Excerpt on propagation methods from Plants for a Future database:

Seed – best sown as soon as it is ripe in a cold frame.When sown fresh,
the seed produces a root about 6 weeks after sowing with shoots formed in
the spring. Stored seed is much slower, it should be sown as soon as
possible in a cold frame but may take 18 months or more to germinate. The
roots are very sensitive to disturbance, so many growers allow the
seedlings to remain in their pots for 2 growing seasons before potting
them up. This allows a better root system to develop that is more
resilient to disturbance.If following this practice, make sure you sow
the seed thinly, and give regular liquid feeds in the growing season to
ensure the plants are well fed. We usually prick out the seedlings into
individual pots as soon as they are large enough to handle, and then grow
them on in a cold frame for at least two growing seasons before planting
them out when they are in growth in the spring.

The Heartland Peony Society has an illustrated tutorial on grafting tree peonies, should you wish to try this method.

dividing and propagating Dierama

Could you provide some information on the propagation and division of Dierama (not sure if the species I have is D. pendulum or D. pulcherrimum. It has pink flowers and is also known as Angel’s Fishing Rod)? The clump has gotten large and I’d like to see if I can divide it now in fall.

The Royal Horticultural Society has an advice page on how to divide and propagate Dierama.

Excerpt:
Named cultivars can be propagated by division in spring or immediately after flowering; but this should only be undertaken occasionally as plants are slow to re-establish. Plants grow from corms that build up year by year into chains, similar to Crocosmia.

  • Lift plants and separate corms, reducing the foliage by half with secateurs.
  • Take care not to damage the brittle, fleshy roots.
  • Divisions take one to two years to flower freely again.

For an answer from local experts, I consulted Perennials: The Gardener’s Reference by Carter, Becker, and Lilly (Timber Press, 2007). The authors say that “it’s best not to transplant, divide, or groom in the fall.” Instead, if you must divide, do so in April or May and include several corms in each clump. You can also sow ripe seed at that time. Seed may be harvested by shaking the stems.

on propagating Abelia

How would you propagate Abelia x grandiflora?

 

According to the American Horticultural Society’s Plant Propagation
edited by Alan Toogood (DK Publishing, 1999), Abelia may be propagated
from softwood cuttings in spring, from greenwood cuttings in late spring,
and from semi-ripe cuttings in early to late summer. “Cuttings… root very readily in a closed case or mist bench. Softwood cuttings from the first flush of root growth in 2-4 weeks. In colder regions, do not pot greenwood cuttings taken after midsummer; prune cuttings into a bushy habit, but allow new growth time to ripen–if not well established, they overwinter badly. Keep semi-ripe cuttings taken in late summer
frost-free. Plants flower in 1-2 years.”

Here are links to general information on propagation from cuttings:

Plant Propagation by Stem Cuttings: Instructions for the Home Gardener, from NC State University

Propagating Plants from Stem Cuttings, from Rainyside Gardeners

propagating Hoya bella

Do you have any information on how to propagate Hoya bella?

 

I consulted The American Horticultural Society’s Plant Propagation (ed. Alan Toogood, DK Publishing, 1999) for information on propagating Hoya. This plant can be propagated by seed in spring or summer, and by cuttings, from spring to summer.

If the seeds are sown fresh and kept moist at 70-81 degrees, they should germinate in a few days. It is more common to increase this plant by cuttings. Cut a length of stem just below a leaf node. The cutting should be 3 to 4 nodes long. Dip its base in rooting hormone (which will also help stop the ooze of sap). Root as you would a stem cutting–fill a pot with a medium of fine grit (top 1/4 of pot) layered on top of gritty cactus soil mix (bottom 3/4 of pot). Gently push the cuttings through the fine grit into the soil mix. Keep slightly damp, but not too humid. If it is not warm enough in your home, provide gentle bottom heat to 70 degrees. They should root in 2 to 6 weeks. New plants will take a year or two to flower.

seed germination of Acer triflorum and Acer griseum

I am interested in the seed germination requirements of Acer triflorum and Acer griseum.

 

There is information in The Reference Manual of Woody Plant Propagation by Michael Dirr and Charles Heuser (Varsity Press,2006):

Acer triflorum seed is “doubly dormant and when fall planted will germinate the second spring and sporadically thereafter. Seed, unfortunately, is often not sound […] Nine months warm followed by 3 months cold gave reasonable germination. If seed is received dry it may be prestratified for 6 months and then sown. Germination is less than 1% the first year but is very good the second.”

The authors state that with Acer griseum, “the biggest problem is poor seed quality” (between 1 to 8% viability). Also, seed production from an individual tree varies widely from year to year. “Seeds are doubly dormant and if fall planted require 2 years, some germinating the third year and beyond. The pericarp wall is extremely tough and dormancy is caused by a physical barrier as well as internal embryo conditions.” Dirr says that he has cold-stratified seed for 90 days, split the fruit wall to extract the embryos, and planted them in vermiculite with a fair amount of success. Growing this tree from cuttings is considered extremely difficult, and grafting (onto seedling Acer griseum seems to be the easiest propagation method.

growing Allium from seed

Could you tell me how to grow Allium from seed?

 

I will assume you are propagating ornamental Allium. According to the American Horticultural Society’s Plant Propagation (edited by Alan Toogood; DK Publishing, 1999), Allium seeds may be sown any time from late summer to early spring. Seeds should be collected when the flower heads turn brown and before the seedpods open. If you tug gently on the flower stalk and it comes away easily from the base, the seed is ripe. Cover the spot where the stalk was removed with soil to prevent entry to pests. With smaller flowering Allium, you can shake seeds directly into a paper bag (without removing stalks). Sow the seeds fresh, or store them at 41 degrees F, and sow in the spring. Germination time is usually 12 weeks, but in some cases it will take up to a year.

The Royal Horticultural Society says that Allium cultivars may not come true from seed, so you may want to consider alternate methods of propagation, such as by offsets or aerial bulbils.

Garden Tip #50

A book by Jekka McVicar called Seeds: the ultimate guide to growing successfully from seed (Lyons Press, 2003, $22.95) will help you turn your seedy hopes into plant reality. Thirteen chapters are divided by types of plant including ferns, grasses, shrubs, perennials and herbs. The practical information that applies to all kinds of seeds, such as what type of soil to use, and how to break seed dormancy, is included in the last chapter. Color photos illustrate throughout.

For online tips for seed starting go to:
http://cru.cahe.wsu.edu/CEPublications/pnw0170/pnw0170.pdf from Oregon State University.