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Stopping raspberries from spreading

We are expanding our vegetable garden, and I wanted to put in a row of raspberries (hardly vegetables but you get the idea). My wife is against it because raspberries spread so many underground roots and sap the energy of the rest of the soil and interfere with other plants. I’m sure she’s right. What do gardeners do to stop the spread of raspberries?

To keep the raspberries from infiltrating the vegetable bed, you could install a root barrier such as gardeners use to contain bamboo. Even more simply, you could set the planting area apart from the veggies with fairly deep edging material–such as one might use to keep grass from invading garden beds. I’m sensitive to proposing something that is a lot of work, but you could make a dedicated raised bed for raspberries along the edge of the vegetable bed. I’m a fairly lazy gardener, and I planted raspberries amongst all my other plants. When the berries run to areas where they are unwanted, I just pull them out. But you will get a better, easier to harvest crop if you provide them with their own area. This Fine Gardening article addresses the issue of running, as well as ideal planting conditions:

Excerpts:
“Raspberries are joyfully exuberant about procreating by underground runners, poking up impressive numbers of healthy new plants all around your original patch. I don’t consider this to be a problem, though, because one whack of the hoe takes care of them. You can also present them to a friend or use them to extend your patch. […] If you have rich, deep soil that drains well year-round, you can simply plant your raspberries in a permanent garden site. Not us. The Pacific Northwest gets rain all winter, and many gardeners lose raspberries to root rot because they make the mistake of planting their raspberries’ fussy little toes directly in the ground, which is often soggy clay covered with a skim of topsoil. We also experience a two-month drought most summers. Raised beds allow us to have deep soil that holds moisture evenly yet drains well.”

on the “Burning Bush” plant

I am looking for more information regarding Rubus sanctus, also known
as the Burning Bush at Saint Catherine’s Monastery in the Sinai. I am interested in this plant because my church group is just finishing up our study of the Book of Exodus. And I thought this plant might make a really nice and symbolic gift.

I am beginning to understand that this plant may be rare, or possibly known by
another name?

 

The problem with English common names for plants of the Bible is that you are at several removes from knowing which plant the original Hebrew text describes. There are some sources which state that “burning bush” refers to Rubus sanctus, but it is more likely that it refers to Senna alexandrina. The Hebrew word in Exodus is sneh, which is the same as the Arabic word for the Senna plant.

Plants of the Bible by Michael Zohary (Cambridge University Press, 1982) says that “the plant in question, specifically named ‘sneh,’ might well have been a real plant in the local flora. As there is no hint in the text that the sneh was a thorny bush, and there are no plants in Sinai or anywhere else that are not consumed when burnt, sneh may be identified linguistically only.” He also suggests that the plant may have been Cassia senna, now renamed Senna alexandrina. There is no native Rubus in Sinai, Egypt, or southern Israel, and the bramble in the monastery garden at Santa Caterina is a cultivated specimen, planted by the monks “to strengthen the belief that the ‘burning bush’ has grown there since the revelation, so completely is sneh equated with brambles in the minds of scholars and Bible lovers.”

While Senna alexandrina may be a bit difficult to obtain, there are other species of Senna more widely available. However, if you wish to grow the Rubus you saw (also referred to as Rubus ulmifolius ssp. sanctus and Rubus sanguineus) as a keepsake from your trip to the monastery, you should go ahead. It is not easy to obtain except as seeds, and it prefers a moist environment.

the fruit infesting Spotted Wing Drosophila

Could you tell me more about a new type of fruit fly that is supposedly infesting fruit here in the Pacific Northwest? Which fruit are affected?

The fruit fly is called the Spotted Wing Drosophila. It is known to affect strawberry, raspberry, blueberry, plum, peach, cherry, and grape. Oregon State University has created an information clearinghouse about this pest. Here is their information for home fruit growers. Washington State University has also devoted several web pages to this fly. Here is their Integrated Pest Management information, excerpted below (SWD stands for Spotted Wing Drosophila):
“Monitor for SWD using traps. […] These vinegar traps are for monitoring purposes only and will not provide control of SWD. Remember, chemical control is not necessary if SWD is not present.
Composting fruit will likely not be effective at destroying maggots and pupae.
Remove infested and fallen fruit. Destroy or dispose of infested fruit in a sealed container.
Management recommendations are currently being developed for this pest. For the time being, good sanitation practices should be used.”

Whatcom County Extension has clear, basic information for home gardeners as well. Since this insect is a relatively recent invader in the Northwest, information is constantly being adjusted and research is ongoing.

controlling whiteflies and recycling grass clippings

I have whiteflies on my orchid Christmas Cactus. How can I get rid of them? I also would like to know if grass clippings are good to fertilize raspberries.

Christmas cactus, or Schlumbergera bridgesii, does occasionally have problems with insects. Whitefly nymphs and adults cause damage by sucking plant juices, and their feeding can weaken a plant. They also secrete a sticky substance called honeydew, which may then harbor sooty mold. For indoor plants affected by this insect, you might try gently washing the leaves. Rodale’s Encyclopedia of Indoor Gardening, edited by Anne Halpin (1980) says that adults are easy to wipe up when it is colder indoors, and the young are usually on the undersides of leaves and may be wiped off with a sponge. Many whiteflies are now resistant to insecticides, and so it is best to start with plain water or soap and water. The book Indoor Gardening the Organic Way by Julie Bawden-Davis (Taylor, 2006) lists sticky traps, insecticidal soap, alcohol spray, oils, and pyrethrin as potential controls. There are products containing Neem oil which could help, if plain water or soapy water don’t control the problem.
Clemson University Extension has some helpful information on general care of this plant.

As for using grass clippings as fertilizer, as long as the grass was not treated with weed-and-feed or other pesticides, it should be a good source of nutrients. Also, avoid using grass which has already gone to seed. Mulch It! by Stu Campbell (Storey Books, 2001) advises not to spread the clippings too thickly, and to let them dry out a bit before using. Here is a link to Virginia Cooperative Extension’s page on recycling grass clippings.

Taylor’s Guide to Fruits and Berries edited by Roger Holmes (Taylor, 1996) says that “reasonably good soil enriched with an inch or two of good compost or a moderate dose of balanced fertilizer each year should provide sufficient nutrients for your plants to thrive. Berry lovers sometimes provide regular doses of foliar fertilizers to give their plants a boost. Absorbed by the leaves in liquid form, seaweed, fish emulsion, and similar organic materials in balanced formulations provide a broad spectrum of nutrients.”

Pests and diseases of raspberries

It appears that my raspberries may have a disease. I noticed some fruiting canes getting
discolored, then curling leaves, then dying completely. I ripped out ones that were dying or dead, but others seem to be showing beginning symptoms.

There are many potential culprits that could be causing the problems you
are observing with your raspberries. It could be a pest, or it could be a
fungal disease. Remember that summer bearing raspberry canes die after bearing fruit. The canes start to look bedraggled even as fruit is ripening. Once all fruit has been picked these canes should be cut to the ground. Next year’s fruiting canes will look healthy and should not be cut down to the ground.

Have you looked inside any of the affected canes after cutting them? If
you have cane borers, you may find that white grubs have burrowed toward
the base of the cane. Crown borers also cause wilting of new growth in
the spring followed by dieback of the cane. Here are links to
information and images so you can compare what you are seeing with your
plants:

Insects and Diseases of Raspberries from University of Illinois Extension.

Pests and Disorders of Blackberries and Raspberries from University of California.

Washington State University’s Hortsense page on Raspberries (see sidebar on left for diseases and insects)

Raspberry root rot information is available in the Pacific Northwest Disease Management Handbook.

Washington State University Extension’s information for home gardeners says:

“Foliage symptoms of root rots. Root rot is usually noticed when leaves
begin to wilt, turn yellow or brown, and die. Symptoms commonly occur
during warm spring or summer weather and may develop in a few days or
take longer. If longer, leaves are generally yellowish and stunted before
they die.

“Root symptoms of general root rot. Root systems are small, dark brown or
black, and rotted. Since healthy roots may or may not have dark surfaces,
determine root condition by cutting or scraping them. All of the inside
of a healthy root is whitish, but the inside of a rotted root is partly
or entirely brownish or blackish. Wash the cutting tool in soapy water
and swab in rubbing alcohol after cutting.”

You may want to bring samples plus photos of the whole plant to a Master Gardener clinic for diagnosis. There is a link to the current clinic schedule on their website.

Once you have identified the source, you can try to address the problems
and resume growing happy raspberry plants. Oregon State University has a guide to growing raspberries which may be helpful.

Spacing and growing butternut squash and raspberry

We’ve bought some butternut squash starts, and from what I’ve read online,
they require a lot of space. This will be my first time growing them. We
have 4′ x 6′ x 1′ raised beds, and I’m wondering if one bed will be big enough to plant 1 butternut squash start. Also, I’ve read that they require staking?
Is this true? What should we do with the other 2 starts that we got if we don’t have room for them in our raised beds? Try planting them directly into
the ground? I’d hate to throw them out…

We also bought a raspberry plant, and I’ve read that they should have 14-18″
for their roots. Again, our raised beds are only 1 foot deep. Would we be
better off digging a hole in the ground?

There is conflicting information in different sources about the amount of space butternut squash needs. Most sources say (as Seattle Tilth’s Maritime Northwest Garden Guide does) the gardener should allow 18-24 inches between plants, which would mean you could plant all 6 starts in one 4′ by 6′ raised bed. Steve Solomon, however, says in Growing Vegetables West of the Cascades that winter squashes require much more space, so that you could only plant two in your 4′ by 6′ bed.

Staking winter squash can be done to save space. There is a pretty good description of how to do it in Mel Bartholomew’s book, Square Foot Gardening. Basically, the vines are planted 4 feet apart in a trench prepared with “large-mesh wire fencing” on 6-foot posts, and twined through the fencing as they grow. He says the stems are strong enough to support the heavy squashes. The technique is also mentioned in Vegetables, Herbs & Fruit: An Illustrated Encyclopedia by Matthew Biggs, Jekka McVicar, and Bob Flowerdew.

As for your raspberry, it will grow faster and better with deep, rich soil. However, raspberries have a tendency to spread by underground runners, so it is often a good idea to contain them in some way. Depending on what is under your raised beds (i.e., soil, sand, concrete) you may wish to plant them there despite the shallow depth, or dig/mound up within the raised bed to improve the soil depth, or plant the raspberry elsewhere.