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Gardening Answers Knowledgebase

Plant Answer Line Question

Keywords: Flowering of plants, Seedlings--Transplanting, Germination, Brugmansia

Can you give me specific directions on how to germinate Brugmansia seed and care for the seedlings. Also, at what age or size do these plants flower?


The following information is quoted from the book Brugmansia and Datura: Angels' Trumpets and Thorn Apples (by Ulrike and Hans-Geog Preissel, 2002, p. 74):

The fresh seed should be sown as early as possible, at temperatures between 64--79 F. Cover the seed with approximately 1/5 (.20) inch of humus, which must be kept wet.

The seed is relatively large and is pressed lightly into the hummus to ensure contact with the moist planting mix. Initially cover the seed box with a glass plate to provide optimal humidity. At temperatures around 68 F, the various species of Brugmansia germinate very differently. As a rule, germination takes between 10 and 20 days. The young seedlings can then be planted out directly into small containers.Young plants that are grown from seed go through an immature phase, easily recognized by the change in leaf shape. The plants do not reach flowering maturity until the end of this immature phase. The length of time before the first flowering varies with the species. On average, most Brugmansia flower for the first time when the plant is between 2.5--5 feet in size. If they are well cultivated, then they will usually reach this size in six to nine months.

Plants grown from seed can look very different. They differ not only in leaf shape and size, flower shape, color and size, but also in other traits, such as susceptibility to diseases or willingness to flower. The possibilities are almost endless and many interesting and valuable discoveries are undoubtedly waiting to be made....

Date 2017-09-27
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Plant Answer Line Question

Keywords: Germination, Propagation, Acer

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.

Date 2018-06-14
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Plant Answer Line Question

Keywords: Lardizabalaceae, Germination, Akebia

I am looking for information about seed germination of Lardizabala biternata. I am wondering what temperature is best for its germination, if it requires light or darkness to germinate, if it needs to be stratified before germination, and the number of days it takes to germinate. I have the seeds started in my greenhouse at 70 degrees under lights and nothing seems to be happening! I have searched the web and looked at all of my reference books, but do not seem to be able to find this information. The seeds came from Sheffield's Seed Co., Inc. (www.sheffields.com). They do not have any information on their website, although on the seed packet it states that more research is needed!


Below is information on propagating Lardizabala ternata from Plants for a Future.

Seed - sow spring in a greenhouse. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in the greenhouse for at least their first winter. Plant out in early summer and, if possible, give the plants some protection for their first winter outdoors. Cuttings of half-ripe wood, 5-10cm long with a heel, June/July in a frame. The cuttings should be put in individual pots. A good percentage. Stem cuttings in spring and autumn.

After locating an article by Dan Hinkley (Washington Park Arboretum Bulletin, Winter 2004), I decided to widen the search to include information on germinating Akebia as well, since they are related.

The California Rare Fruit Growers site has Akebia germination information that might be useful.

The Royal Horticultural Society A-Z Encyclopedia of Garden Plants only says that Lardizabala seed should be sown in containers in a cold frame in spring.

Date 2017-09-27
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Plant Answer Line Question

Keywords: Gaultheria, Woody plant propagation, Germination

What specific requirements are needed to germinate Gaultheria procumbens in soilless media?
Any tips on seed stratification, cultural advice, etc., etc.?


The information below comes from the website of Plants for a Future:

"The seed requires a period of cold stratification. Pre-chill for 4-10 weeks and then surface sow in a lime-free compost in a shady part of the greenhouse and keep the compost moist. The seed usually germinates well, usually within 1- 2 months at 20 c, but the seedlings are liable to damp off. It is important to water them with care and to ensure that they get plenty of ventilation. Watering them with a garlic infusion can also help to prevent damping off. Prick out the seedlings into individual pots when they are about 25mm tall, and grow them in light shade in the greenhouse for at least their first winter. Plant them out in late spring or early summer. The seedlings are susceptible to spring frosts so might need some protection for their first few years outdoors. The leaves remain very small for the first few years. If you want to grow from cuttings, use half-ripe wood 3-6cm long, and in July/August place in a frame in a shady position. They form roots in late summer or spring. A good percentage usually take. Division can be carried out at almost any time of the year, but works best in the spring just before new growth begins. Very easy, larger clumps can be replanted directly into their permanent positions, though it is best to pot up smaller clumps and grow them in a cold frame until they are rooting well. Plant them out in the spring."

I consulted the book, Seeds of Woody Plants in North America by James A. Young (Dioscorides Press, 1992, rev.ed.), and the general information on Gaultheria states that cold dry storage will help maintain seed viability. G. procumbens has 6800 seeds per gram. Seeds are initially dormant and prechilling is needed for germination (from 30-120 days with a variety of substrata). Salal (G. shallon) seeds appear to require light for germination. This resource says that G. procumbens seeds should be sown in the fall.

Date 2018-04-11
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May 31 2018 13:14:08