How to harvest new crop of asparagus

Jacquie Becker asks: I planted asparagus two years ago, knowing I needed to wait a couple of years before I could start harvesting. They are starting to come up now and are looking really good. How will I know when to stop harvesting and what's the best way to cut them?

You can harvest the asparagus for about six weeks, then in subsequent years, you can extend this to eight weeks or so. Cut the individual spears with an asparagus knife, available at most nurseries, or use a sharp knife roughly ¾" below the soil level. Harvest all the spears, including the thin and crooked shoots, as this will help to promote new growth later on.

Topdress the soil with an all-purpose fertilizer and cover any bare soil with 2 inches of composted organic matter. This will help continue to feed the plants as they grow.

After the six weeks, allow the foliage or "ferns" to continue to grow as this will help strengthen and feed the crowns during the growing season. Do not cut back the foliage until it has died down naturally.

Carol H. of Healdsburg asks: Every so often, a shoot from one of my plants, in this case, a rose bush, grows in a very distorted way . . . . Like someone flattened it out with a roller. The shoot is thick and very odd looking. It doesn't happen very often, but when it does, it's quite noticeable. Why does the plant do this, and is there a name for it?

Fasciation is one of the most unusual looking disorders gardeners commonly see on plants. This strange phenomenon affects a wide variety of plants. The stems usually become enlarged and flattened, often developing a ribbed look to it. The flower stems can also be affected, although it's less common, with the flowers and buds developing on the distorted, flattened stems.

It is thought that fasciation results from unusual activity in the growing tip. This could be caused by insect, disease, frost ,or mechanical damage. It's also possible that viral or other infection could be the cause.

Although fasciation looks rather strange, it is harmless and will not affect the vigor or health of the plant. If you think it's unsightly, then just prune out the affected stems back to normal growth. There's no guarantee that other shoots will not be affected.

Mary Romano and Ruth Schurbert of the Rohnert Park Garden Club both add banana skins to their potted rose bushes because that's what someone told them to do. They either lay them on top, or dig a hole and bury them. What, if any, nutrients do the bananas provide, and should they continue to add them?

Bananas are rich in both phosphorus and potassium which are important macro-nutrients plants need. Rose bushes in particular benefit from added potassium. Banana peels are a natural source of the phosphorus and potassium found in expensive fertilizers, so why buy when making your own banana fertilizer is as easy as tossing the skins? As long as your roses are green and growing and look good, then continue to feed them their banana skins!

Ellen Anderson of Sonoma asks: I have a large Magnolia x soulangeana (Tulip tree), that is doing quite well. Is it necessary to do any sort of pruning on these trees? What should I be looking out for?

Established Magnolias usually need very little pruning. Broken or criss-crossing branches should be cut out and this should be done in midsummer when the tree is in full leaf. This will give the pruning cuts time to heal before winter, making them less susceptible to dieback. Large cuts into old wood are best kept at a minimum.

Magnolias can be slow to heal, and new growth may not begin until the second season after pruning. 'Water sprouts' may develop after pruning and those should be removed to maintain the shape of the tree.

Dana Lozano is a horticultural garden consultant and designer. Gwen Kilchherr is an arborist, garden consultant, and horticulturist. They are partners in a Windsor horticultural consulting and design business, The Garden Doctors. Fax questions to them in care of the Press Democrat at 521-5343.