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**Currently there is no master gardener available to answer your questions. The site editor, Charlotte Gerber, will be answering questions in the interim.

Current Question: Asparagus Bed

How do I start an asparagus bed? I live in N.E. Arkansas.

Thank you, Loyd McIntire

Expert Reply

Dear Loyd,

Asparagus is grown in trenches. Preparing the bed the old-fashioned way is a lot of work, but a well-made bed will grow delicious asparagus for fifty years with only annual top-dressing and hand cultivation. Asparagus should be grown in a sunny location, quite far away from any trees.

Traditionally, an asparagus trench is dug about eighteen inches wide and about two and a half to three feet deep. If this takes you down into compacted subsoil, remove it. Fill the bottom of the trench with a drainage layer of rubble or gravel, followed by a foot or eighteen inches of rotted manure. Top it up with good garden soil mixed with compost. The roots, which are traditionally called 'crowns', are planted about ten inches below the surface and about two feet apart.

Many modern growers dig shallower trenches, twelve to eighteen inches deep. Sprinkle a balanced 10-10-10 fertilizer on the bottom, and fill it three-quarters of the way with garden soil. The top four inches or so should be compost. The crowns are planted five to eight inches below the surface of the soil. These shallow asparagus trenches are usually heavily mulched.

Remember that asparagus should be allowed to grow for several years before harvesting, so that the plants are well-established and strong. Asparagus will self-sow, but you don't want to encourage that until the bed is completely established, so pull out any stalks that develop berries. Cut down the foliage each fall.

~~Lou

Previous Questions

Locust tree in office

In our work office we have a Locust tree. I do not know a lot about it, however it is 2 yrs old and the leaves are starting to turn a yellowish color. It is in a office with lots of sunlight and I need to know what to do to keep it alive. The care instructions for this would be greatly appreciated. Thank you in advance for your time. I hope to hear from you soon.

Fondly, Annelise Bello

Expert Reply

Dear Annelise,

The black locust tree (Robinia pseudacacia) is a North American native that was introduced to Europe around 1630. It is fast-growing and tough, which has made it a popular street tree. It is deciduous. New cultivars grow to smaller heights and are thornless; some are popular for bonsai. Your office tree may be one of these cultivars.

Because their roots are so restricted, trees planted in pots require more care.

• Water

Is your tree getting enough water? It should be watered deeply two or three times a week, enough so that the water gets to the bottom of the pot and drains out. The pot should be resting in a large saucer, so that the water doesn't go all over the floor. You can't tell if it needs water just by feeling the surface. Get your hand deep into the soil to see if it is damp or dry. A layer of mulch over the surface will help keep the soil evenly moist.

• Drainage

Make sure the pot's drainage holes aren't blocked. If they are, your tree's roots will be sitting in very wet soil, and root rot is a real threat. Your pot should have a layer of coarse material -- ranging from potsherds to styrofoam pellets -- in the bottom to help with drainage.

• Fertilization

If your tree was planted in a soilless growing medium, it will get no nutrition through its roots. If it was planted in potting soil, the nutrition has probably been absorbed from the soil over a two-year period. You can use a liquid fertilizer for potted trees. Usually a dilute mixture once a week is best. Alternatively, you can use time-release fertilizer pellets. Work them into the soil.

• Root Growth

Plants in pots can't extend their roots down into the soil the way that plants in the garden can, so they often become rootbound. The roots typically grow until they hit the walls of the container. Then they bend and grow around inside the container. In a houseplant, the solution is to repot the plant in a larger pot filled with fresh soil. This works well for trees grown in pots too, but you may not have enough space for the larger pot and the increased topgrowth that results from repotting. You may need to resort to root pruning. It's not as hard as it sounds. You remove the tree from the pot, brush away some of the soil, and prune away some of the roots. Try not to take more than one-quarter of the root growth. Gently loosen some of the remaining roots from the root ball. Then repot the tree in fresh soil. Water it thoroughly. It may look droopy for a day or two because of transplant shock, but soon it will be thriving. You may want to prune just a little of the topgrowth as well.

Trees in containers sometimes suffer from root girdling. A root that is bent or twisted can grow sideways and backwards until it makes a complete circle around itself or around another root. Then the trapped root is gradually chooked off, so that it can absorb water or nutrients, and the entire tree suffers. If you see a girdling root when you take the tree out of its pot, prune it away.

How lovely to have a tree in your office! Enjoy!

~~Lou

Jasminum mesnyi

Hello, I live in Northeast Florida and have a lovely vine which I planted four years ago that had a label of "Japanese Jasmine". I suspect that I have a Yellow Jasmine as my plants' flowers are not double blooms but single (approx.) 1" blossoms that send the most delicious fragrance out on the wind. My plant has finally seeded (en mass!) and I would love to know how to germinate the seeds. Many have simply fallen on the ground in the garden under the vine, but I would like to start and keep several of the plants indoors. There are 26 seeds in each pod and I've collected nearly a thousand seeds! Thank you so much for your assistance!

Gwendolyn R.

Expert Reply

Dear Gwendolyn,

If your plant really is Jasminum mesnyi, you have something exciting there, because Jasminum mesnyi seldom seeds.

Jasminum mesnyi is sometimes listed as Jasminum primulinum and is known by the common names of Japanese jasmine, primrose jasmine, and yellow jasmine. The plant is native to southwestern China. It was introduced to English gardens during the Victorian period, but it was grown from cuttings instead of seed. The famous plant collector E. H. Wilson, who worked for Veitch's nurseries, had not been able to find any seeds. More recently, researchers at the botanical garden of Heidekberg attempted for several years to achieve fruit-set in jasminum mesnyi by artificial pollination, but had no success. After they ended the project, the plant produced four fruits. Jasminum mesnyi is not self-pollinating. Researchers in Australia reported that both honeybees and crab spiders are frequently found on Japanese jasmine.

You will have to experiment with seed germination. Try leaving some of the seeds in the garden where they fell. Keep the weeds away, water them occasionally, and wait. Remember that perennial seeds often have a long dormant period, and that some seeds may germination before others. Try sowing another group of seeds in trays, following the directions in our article on seed germination.

If the seeds don't germinate, you can still have more plants, because jasminum mesnyi is extremely easy to propagate by layering or cuttings. It tends to root wherever the tip of a branch touches the ground. Left to itself, it grows like a fountain-shaped shrub about eight to ten feet tall, and will soon become a thicket. As your plant grows older, you may have to prune it to keep it from taking over your garden!

Jasminum mesnyi is often recommended for erosion control because it roots so easily. In some parts of the southern US it has grown into flowering hedges along the highways where it was originally planted. It's evergreen in really warm climates but dies back to the ground after a sharp frost. It blooms on the previous year's growth, so prune out old growth after the plant blooms. It can be grown like a vine with proper support or like a shrub. This is an easygoing plant, growing in part shade to full sun and in a variety of soils. It doesn't like boggy conditions, but it will tolerate some dryness after it is established. Deer usually avoid it.

~~Lou

Frost-damaged Aloe Vera

I have a beautiful LARGE Aloe Vera plant that I have had as a house plant for over a year now. I was living in Mobile, Alabama, where I could leave the plant on the porch. Now I live in Atlana, Georgia, and I had the plant on the patio, until we had some freezing temperatures one night. I realized I had left the plant out and brought it in the next morning. The plant is wilting. It has "seeped" some fluids, some of the partial leaves are still firm while others are completely withed, the most center leaf is still bright green and standing tall.

Now my question is what do I do to attempt to revive the plant? Do I cut the wilted leaves at the base, leave them alone ?? Please if you have any advice, guide me.

Thanks, Cyndi

Expert Reply

Your aloe has certainly been damaged by the frost, but it sounds as though the roots and the growing crown have survived. That's good news! Bring the plant inside until the cold weather is over to avoid additional damage.

Trim back the damaged leaves. You can take them all the way back to the soil if they're severely damaged, or just cut back to healthy material if they're only damaged at the tip. Dry the cuts as much as you can. Succulents are prone to rot in moist, damaged tissue.

Water the plant lightly, and in a few days, give it a very light feeding with a balanced fertilizer. It should look better in a few weeks.

~~Lou

Where can I get the following plants?

Where can I get the following plants : Brachyglottis repanda var. "purpurea", pittopsorum tenuifolium var. "yellow wave", Pittosporium tenufolium var. " Waimea" ? I am trying to build a large collection of unique plants. I live in South West Ireland and many southern hemisphere plants thrive here. Also, are there an leucadendron varieties capable of growing here ? Jim Costello

Expert Reply

These nurseries list the plants you named. I have never dealt with them, but they should be able to advise you about plants suitable for your area as well as import regulations.

• Brachyglottis repanda var. purpurea - Hardy Exotics Nursery in Cornwall
• Pittosporum tenuifolium 'Yellow Wave' - BlueBell Nursery in Leicestershire
• Pittosporum tenuifolium 'Waimea' - Lyndale Liners in Auckland

Celmisia Spectabilis

I have recently purchased seed for CELMISIA SPECTABILIS for my father. Unfortunately, I received no information with them as to how to plant, when to plant, etc. My father and I would appreciate any details you can provide.

Expert Reply

Celmisia spectabilis – also known as cotton plant, shepherd’s daisy, and mountain daisy or by its Maori name, tikumu -- is an subalpine perennial native to New Zealand. You will have better results growing these plants from seed if you can duplicate their natural growing conditions.

Mountain daisy grows at altitudes ranging from 980 to 5575 feet, where it may experience winter temperatures as low as 0 degrees Fahrenheit. It thrives in grasslands, getting lots of sun and rainfall. Soil is usually slightly acidic and, typical of mountain growing conditions, has very quick drainage.

Celmisia seed should usually be sown directly after harvest, when it is fresh, although seed will not germinate until after it has experienced winter conditions. You can check our article on seeds for more information about scarification.

Seeds germinate at irregular intervals over an extended period of time. This is an advantage in the wild, but it can be frustrating to gardeners. Be patient as you watch for seedlings to appear. Even moisture and cool temperatures (less than 41 degrees F) are helpful. Shield the seed bed from direct sunlight.

If you don’t live in an area that will provide a good winter chilling period, or if you prefer to start your seeds in a tray instead of in the garden, you will have to provide an artificial chilling period. Try keeping the seed tray in a refrigerator for a month. Place the tray in a lightly shaded location when you take it out. Seeds will usually begin to germinate in about 14 days after chilling.

Star Jasmine

I am concerned about my Star Jasmine plant. After all the cold weather, the leaves have started to turn a brownish/red color (like fall leaves). Otherwise it looks healthy. I keep it in a pot on my deck - where our lows in the winter normally get to the low 30s, the cold snap dropped down to the low 20s. The plant is at least a couple years old. Is this normal or is there something I should do?

Expert Reply

It sounds like your star jasmine has suffered from freeze damage. Typically, their leaves and stems turn a reddish color when injured by frost. Prune out the damaged areas and continue with ordinary good care, and your plant should bounce back as long as it is not frosted again.

Remember that plants in pots are more vulnerable to damage from cold than plants in the ground. If cold temperatures are forecast, cover the plant. Even a light sheet of plastic will provide protection from frost – or if you’re really desperate, grab some bed sheets.

If a heavy frost catches you by surprise, it sometimes helps to spray the frosted foliage with tepid water. You have to do this very early, before sunlight hits the frosted leaves, to prevent tissue damage.

Trachelospermum jasminoides, called star or Confederate jasmine, is usually recommended for zones 8 and warmer, with a few cultivars recommended for zone 7. Experienced gardeners will tell you that individual plants show very different tolerances for cold, with some flourishing despite the occasional sharp freeze or light snow while others die after a relatively light freeze. Even if you have a particularly tender plant, you should be able to bring it through cold snaps safely and enjoy that beautiful scent next spring!

Rose Tree of China

Hi, I live in Wasilla, Alaska and would like some info on how to care for my Rose tree of China. I've been looking high and low on the internet for info and have no such luck. If any one out there knows anything about the tree I would love some expert advice. Thanks for any help.

Expert Reply

I suspect that your Rose Tree of China is probably Prunus triloba ‘Multiplex’, which can be grown as a small tree and was introduced to the U.S. from China in 1885.

‘Multiplex’ is the most widely-grown varietal. It has pink flowers in early spring. ‘Simplex’ produces small red fruit that is very attractive to squirrels, but ‘Multiplex’ is sterile. It is usually grown as a multi-stemmed shrub that reaches ten to fifteen feet in both height and spread, but it can be trained to grow as a standard or can be grafted onto a single stem and grown as a small tree.

Branches cut in late winter or early spring can be forced into bloom indoors. Prunus triloba responds well to pruning and can be trained in a variety of shapes. It is sometimes grown as bonsai. Pruning encourages heavier flowering.

‘Multiplex’ grows well from zone 7 to zone 3. The map looks as though Wasilla is in zone 3, so you should have no difficulty overwintering it. However, the flower buds can be damaged from late frosts.

Prunus triloba should be grown in full sun for best flowering, but usually will flower in part shade as well. It prefers a rich, slightly acidic loam. Even moisture is best, but an established shrub will tolerate some drought. Some authorities suggest that ‘Multiplex’ should be grown surrounded by groundcover or in a mulched bed, since it does not recover easily from injury.

Prunus triloba ‘Multiplex’ is susceptible to verticillium wilt. Other potential diseases include leaf spot, die back, powdery mildew, cankers, and black knot. It is likely to be attacked by a variety of insects, including aphids, scale, borers, caterpillars, tent caterpillars, Japanese beetles, and spider mites. If you suspect any of these problems, consult an expert for diagnosis and treatment.

I hope this helps. Enjoy your beautiful tree!

~~Lou