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Search Results for ' Yucca'

PAL Questions: 3 - Garden Tools: 1

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Keywords: Rooting, Yucca, Propagation, Transplanting

PAL Question:

I have a number of large Yucca plants in my yard that I would like to dig up and transplant. I am not entirely familiar with this type of plant, but have noticed that, likely due to the age of these plants, several trunks have sprouted from the mother plant and have begun growing as what appear to be separate plants. However, these extensions are easily lifted from the ground and show no evidence of independent root development. Can I cut the new plants from the original plant and get these to take root elsewhere?

View Answer:

Following is some information that may help you in transplanting your Yuccas.

TRANSPLANTING

From Agaves, Yuccas and Related Plants: A Gardener’s Guide by Mary & Gary Irish (2000, pages 65-68)

    In mild winter climates that have hot summers, particularly hot and dry summers, fall planting is best, so that root systems establish through the mild winter before the onset of the stressful summer season. If planted in early spring, plants must be carefully watered and shaded from the sun during the summer to prevent sunburn and debilitating heat stress…When planting agaves [& yuccas], regardless of the soil type, raise the center of the hole slightly, just an inch or so, and plant the center of the plant at the top. The crown of the agave [or yucca] particularly is susceptible to infections, and when the soil inevitably subsides after planting, the crown can sink below the soil line. The practice of raising the center of the planting hole slightly is helpful in all the stemless members of both families to prevent crown rots.

    For all plants, begin by digging a shallow hole no more than the depth of the root system….Backfill the planting hole without soil amendments or with a very small amount of compost. Tamp the soil lightly as it is backfilled to prevent excessive settling later...

    Moving mature arborescent plants, such as some members of Beaucanea, Furcraea, Nolina or Yucca, is more difficult. These large plants are sensitive to root and stem disturbance, and wounds of the basal growing platform in Yucca can introduce a host of infectious agents into the plant. If possible, it is much more advisable to move such plants when they are young and nearly stemless.

PLANTING TOES & SUCKERS

From American Horticultural Society Plant Propagation by Alan Toogood (1999, p. 145)

    TOES

    Uncover the roots of a mature plant. Remove swollen buds (toes) from the parent rhizome, cutting strain across the base of the toe. Pot each toe singly in a free-draining medium, at twice its depth. Water. With bottom heat (59-68 F) the toe will root in 2-3 weeks.

    SUCKERS

    In spring, carefully uncover the base of a sucker. Cut it off at the base where it joins the parent rhizome. Dust the wounds with fungicide. Pot the sucker singly in a free-draining medium, such as equal parts soilless potting mix and fine grit. Keep at 70 degrees F until rooted (12 weeks).

Season All Season
Date 2007-04-20
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Keywords: Sheet mulching, Yucca

PAL Question:

Our home in Seattle came with a large number of established Yucca plants, and we would like to get rid of them. However, they are quite stubborn. We've tried a few things, including digging them up, but the root system seems quite deep and extensive and they always come back, and quickly! Any suggestions? I've thought they were non-native, but I guess they could be the sort that are found in eastern WA. Are there invasive species here in western Washington?

View Answer:

As you have observed, Yucca is very difficult to eradicate completely. Most of the literature on the subject suggests using herbicide, but even this may be ineffective, which makes the risk of using harmful chemicals to control the plant seem even less worthwhile. There are quite a few informal discussions on how to get rid of this plant on various online gardening forums, and one mentions local gardening expert Ciscoe Morris's method for getting rid of unwanted Yucca:

"...he cut it back to ground level and put a couple of squares of heavy cardboard over it, piled on some compost/bark to hide the cardboard. I'm not growing yucca, but he said it really worked for killing it without breaking your back. Leave in place for a year."

The technique described here is called sheet mulching. This involves laying down overlapping layers of cardboard and then covering thickly with leaves, compost, and other materials. Agroforestry.net offers information on how to do this. StopWaste.org provides additional helpful information.

Here is an excerpt from an answer to a question similar to yours, written by one of my colleagues here at the Miller Library:

"The general idea is you spread out a layer of cardboard or newspaper (about 4-6 sheets) and then cover that with a layer of organic mulch (compost, straw, alfalfa hay--available at feed stores, wood chips, coffee grounds, etc.). Then wait 6-8 months. This is not an exact science because there are many variables, such as thickness of newspaper, type of mulch and what type of plant you're trying to kill. Perennial weeds and especially coarse grass will push through the cardboard once it starts to break down so it is critical that if and when this happens you pull the mulch back and put down more newspaper/cardboard, and then replace the mulch."

Yucca is not (yet) considered invasive in our state. Here are links to information on locally noxious weeds.
Washington Noxious Weed Control Board.
King County's Noxious Weed Control Program.

Season All Season
Date 2007-07-11
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Keywords: Yucca, Seeds

PAL Question:

I live in New Mexico, and I'd like to harvest Yucca seed to share with the local cactus and succulent society. Last time I tried, I didn't find any seeds at all. I want to go about this the right way--can you tell me what I should do?

View Answer:

In searching for an answer to your question about how and when to collect seed from Yuccas, I came across several articles on the interdependence of Yuccas and Yucca moths. Here is one example, from Emporia State University:
Excerpt:
"... the yucca plant and yucca moth are the textbook case of coevolution. First, the yucca plant has no ability to reproduce seeds without the moth. Yuccas can propagate small rosettes around the parent plant, but these vegetative sprouts are copies of the parent. Over decades, the plant cannot move but a few feet, and there is no possibility for genetic variation. Without the moth, the whole flowering effort (expensive to the plant in energy terms) is a total waste. The only pollinator of the plant is the yucca moth; bees are not attracted and neither wind nor bees can pick up the sticky pollen.
The yucca moth is likewise dependent upon the yucca plant. There are no alternate host plants known for the yucca moth; the yucca moth caterpillars must eat yucca seeds or starve. Without the plant, the moths die off in one generation. Without the moth, the plant cannot reproduce variation or disperse; given any major climate changes, it too will go extinct. The system is therefore tightly coevolved.[...] You can watch yucca moths pollinate flowers between dusk and midnight. The female gathers pollen from the flower anthers by using her specially adapted mouthparts, called palps. She forms the sticky pollen into a ball which she carries between her tentacles and her thorax (under her "chin" so to speak). The pollen ball is then "stuffed" or "combed" into the stigma of the various flowers she visits. The stigma is the receptive tip of the female pistil. Without this process, the yucca flower will not develop into the fruit or pod with seeds."

The Arizona-Sonora Desert Museum states that Yucca may not set seed every year:
"Biologists have only recently determined that almost every species of yucca has its own species of yucca moth; some yuccas have two moth species. Such a tight mutualism has risks for both partners. Emergence of adult moths must coincide with yucca flowering for the reproductive needs of both species to be met. However, the synchronization of moth emergence with flowering is frequently poor and seed set and moth reproduction in such years are low. Furthermore, yucca populations may flower sparsely or not at all in dry years. Yuccas don't have to set seed every year because they flower many times in their long lives."

Regarding seed collecting and preparation, a question similar to yours was answered by the Lady Bird Johnson Wildflower Center:
"Gather capsules as they begin to dry but before they split. Allow to dry, then crush to remove seeds. Overwinter, keep seeds in moist sand in the refrigerator. For longer storage periods, keep in sealed, refrigerated containers.
At the Lady Bird Johnson Wildflower Center, we have collected and prepared yucca seeds for the Millennium Seed Bank. Crushing the pod to remove seeds is not as easy as it sounds. We found that pliers worked about as well as anything, but it was a struggle, either way. Inside the broken pod, you will find channels of seeds. They are flat, black wafers, very thin. As you pull out a stack of them, you may find a neat, round hole drilled up the center. This is the nursery for the larvae of the yucca moth, who have been munching on the seeds. However, the yucca moth is essential for the blooming of the plant."

Late summer to early fall (September/October) seems to be the time when some Yucca seeds ripen. Several places I looked suggested this is the case, including Plants for a Future database, which describes propagation for several species of Yucca.

Season All Season
Date 2010-07-01
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Keywords: Agavaceae (Agave family), Yucca, Reference books, Lewisia, Cactaceae (Cactus family), Xeriscaping, Succulent plants, Sempervivum, Sedum

Garden Tool: Ready for a truly drought tolerant garden? Plant hardy cactus and succulents. The only requirement for these plants is perfect drainage. Hardy succulents can die of rot in our winter wet. Overcome that challenge by building raised beds and mixing plenty of gravel and sand into the planting hole. The book Cacti and Other Succulents by Keith Grantham and Paul Klaassen (Timber press, $34.95) reports the following plants are good candidates for growing outside: Cacti - Echinocereus triglochidiatus (hedgehog cactus), Opuntia humifusa (prickly pear cactus) and Coryphantha vivipara (pincushion cactus); Succulents - Delosperma cooperi (ice plant) and Calyptridium umbellatum (pussypaws); Old Stand-bys - Yucca, Agave paryi, Lewisia cotyledon, Sedum and Sempervivum.

Season: All Season
Date: 2007-04-03
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June 24 2013 12:55:25