Citrus On The Sucker List

90501thumbA five pound kumquat is a problem! It means something went seriously wrong. Anyone who grew one would concur. They are huge, lumpy, and very insipid, with ridiculously thick pale yellow rind around a small handful of uselessly fibrous pulp. They are protected by dangerously sharp and rigid thorns that can get longer than three inches. Even their irregularly wavy foliage is unappealing.

In reality though, there is no such thing as a five pound kumquat. These huge but useless fruits, as well as the associated thorns and foliage, are those of ‘shaddock’, which is the most common ‘understock’ for almost all grafted dwarf citrus trees. It is what keeps such trees compact, so that they do not get as big as orchard trees. It was there all along, whether we were aware of it or not.

Most citrus trees are composed of two genetically different parts. The understock are the lower parts that develop roots that are unseen underground. The desirable upper parts that produce the familiar citrus fruits grow from ‘scions’ that are grafted onto the understock. Graft unions are just above grade, where the texture of the bark above is slightly different from that of the bark below.

‘Suckers’ are stems that grow from the understock below the graft unions. Because they are genetically identical to the understock rather than the scions, they produce the same fruit and exhibit the same physical characteristics as the understock would if it were growing wild. Suckers can overwhelm desirable scion growth, which is how kumquat trees can produce huge five pound fruits.

Other grafted trees and shrubs, particularly fruit trees, get suckers too. New suckers appear as new spring growth develops. They should be peeled off of the main trunks rather than pruned off. As brutal as this seems, it is more efficient than pruning. Soft young shoots should snap off quite readily. This technique removes more of the callus growth at the bases of the suckers, which could develop more suckers later. Big older suckers should be pruned off as closely and neatly as possible.


Vines Are Naturally Social Climbers

70906thumbIf more of us knew how vines compete in the wild, fewer of us would grow them in our home gardens. Understory plants that are satisfied with the sunlight that reaches them through a higher forest canopy are the most passive. Taller trees compete for sunnier exposure above. Vines are the most aggressive as they climb and overwhelm trees to get the best exposure on top of everything.

English and Algerian ivies happens to be among the more efficient of aggressive vines. While young, juvenile growth creeps along the ground searching for victims. Once it encounters something to climb, the stems develop aerial roots so that they can climb vertically. Once the climbing stems reach the top of the support, they develop shrubby adult growth that blooms and produces seed.

In home gardens, ivy is a popular and practical groundcover. However, if allowed to climb as a vine, it can root into walls and ruin paint. Even if the vines are removed, the unsightly aerial roots remain. The shrubby adult growth can overwhelm and even shade out and kill the trees or shrubbery that originally supported it. If it climbs onto a roof, it can accumulate debris and promote rot.

Creeping fig is even nastier. Its network of clinging vines grafts together as it grows, and then strangles the supportive trees as they continue to grow within the constrictive network of grafted stems. Yet, it and Boston ivy work nicely and harmlessly on concrete freeway sound-walls where their aggressive behavior is a major advantage, and their clinging aerial roots are not a problem.

Wisteria and red trumpet vine are considerably better behaved, but even they will crush lattice and anything else they wrap around. If they get into trees, they quickly grow out of reach. They may seem to be more appealing than the trees that they climb are, but can strangle and kill substantial limbs. Even without aerial roots, red trumpet vine clings with holdfast discs that damage paint.

Even though many vines are practical for home gardens, their personalities need to be considered. Star jasmine and honeysuckle can either grow as groundcover or as climbing vines. They can get big, but are not often destructive. Potato vine works nicely on fences, but gets aggressive in trees. Carolina jessamine, lilac vine and mandevilla are some of the more complaisant of vines.

Gophers Go For Spring Vegetation

90424thumbHibernation is a luxury enjoyed by different animals in different climates, where much colder weather inhibits activity through winter. Gophers take no such extended time off here. They merely work less diligently through the cooler and rainier times, and maybe get out of the way if the soil they live in gets too saturated. Their minimal damage had probably been easier to miss or ignore.

Now it is spring! The weather is warming. The soil is draining. All the roots and vegetation that gophers eat are growing. The gophers that were here and somewhat active all through winter are really making a scene now, as they clean mud from their homes and excavate new tunnels. Babies are growing up fast and leaving home, and excavating new homes of their own. What a mess!

Many of the primitive techniques that were used in the past to mitigate gopher problems are ineffective, impractical or even dangerous. Pouring gasoline into tunnels and waiting a few minutes to ignite the fumes can start fires anywhere such tunnels resurface, and possibly out of view! Bare razors dropped into tunnels are potentially dangerous to anyone who happens to dig them up later.

Traps take some work and experience to set properly, but are still the best way to deal with gophers. They do not involve poison that can be dug up and eaten by someone else, or eaten by a gopher who staggers from underground to get eaten by someone else. As long as dogs are not allowed to dig them up, traps are likely only be dangerous to gophers and those setting the traps.

Conventional traps are set in pairs, in each of both directions of a lateral tunnel that is found by excavating back from the tunnel under an active gopher volcano (pile of displaced soil). Once set, the tunnels must be back filled to eliminate air circulation into the tunnel, which would warn a target gopher of intrusion. A bit of weedy vegetation added before back fill might help attract a gopher.

Setting gopher traps is easier to read about than to do safely. It is best to learn how to do it from someone who is proficient at it..

Plant Problems Are Sometimes Exaggerated

04It is not easy for wild trees to adapt to a refined landscape. After a lifetime of adapting to their native environment and dispersing their roots to where the moisture is through the dry summers, they must adapt to all sorts of modifications such as excavation, irrigation and soil amendment. Newly installed plants grow into a new landscape while some mature trees succumb to disease and rot.

Oak root rot is such a common disease in California that there are only a few places where it is not found in the soil. It is not often a problem to new plants, but often becomes a problem to mature trees that suddenly get more water than they are naturally adapted to, particularly if roots have been violated, and the soil has been amended to retain more moisture. Change is not always good.

However, many of the same trees that are so susceptible to oak root rot if the environment around them changes can be remarkable adaptable as young trees. California sycamore happens to be a riparian tree that naturally grows near water. Although old trees may not adapt well to change, young trees planted in new landscapes will adapt to the water that is available as they mature.

California sycamore trees that are adapted to landscape or lawn irrigation are not likely to be bothered by oak root rot until they get old. Realistically though, any old sycamore is susceptible to oak root rot. The only difference is that those that get more water mature faster, so get old sooner. A California sycamore tree planted into a home garden may live only one century instead of two.

Verticillium wilt is another disease that can be found in most places throughout California. It is notorious for severely disfiguring and killing ash trees and many other plants. However, it needs moist soil in which to proliferate. Because lawns are irrigated so frequently and often excessively, ash trees in lawns are innately susceptible to verticillium wilt. In situations that are not irrigated so frequently, newly planted ash trees can mature into healthy shade trees.

Citrus And Avocado From Seed

71227Is it possible to grow citrus from seed? The quick and simple answer to that question is, “Yes.” After all, many cultivars of citrus were originally bred from other cultivars, and then grown from seed. But of course, this an overly simplified answer to an unrealistically simple question about a surprisingly complicated process. Perhaps a better question is “Should citrus be grown from seed?”.

Almost all citrus are grafted for a variety of reasons. Those that are not grafted are grown from cuttings only because they do not need whatever advantages understock (or rootstock) provides for their counterparts. Either way, they are all cloned by some form of vegetative propagation. This ensures that they are all genetically identical to their parents, without potential for genetic variation.

Citrus have been bred and developed so extensively that most types are very genetically variable. Those that are the most variable tend to produce fewer seeds, and might even be classified as seedless. Those with more seeds are probably more genetically stable. Nonetheless, it is impossible to predict if seed grown citrus will resemble their parents, or be something totally different.

Furthermore, citrus are cloned from ‘adult’ growth that is ready to bloom and develop fruit. Those grown from seed start out with vegetative ‘juvenile’ growth that will not bloom. Juvenile growth is typically more vigorous and thornier than adult growth, and possibly wickedly thorny! Some types of citrus outgrow their juvenile phase quite readily, while others may take several years to do so.

Avocado trees grown from seed exhibit some of the same difficulties. Although they lack thorns, they do grow very vigorously and very tall for quite a few years before they bloom. By the time they develop fruit, the fruit could be too high to reach, and quite different from the original.

Just because citrus and avocados can be grown from seed does not mean that they should be. However, different is not necessarily bad. Many seed grown avocado trees get pruned into

Spring Fashions For Vegetable Gardens

60406thumbCompared to replacing cool season annuals with warm season annuals, the replacement of cool season or ‘winter’ vegetables with warm season or ‘summer’ vegetables is not quite as traumatic. Most of the cabbage, broccoli and cauliflower plants finish in time to make room for new vegetable plants anyway. Unlike flowering annuals, they make it obvious that they are done for the season.

If left too late into warming spring weather, the juvenile floral buds of broccoli and cauliflower will bloom, and become tougher and somewhat bitter. Cabbage does the same, but only after bolting first. (‘Bolting’ is the emergence of tall floral stalks from formerly basal foliage.) By the time beet, carrot, turnip and radish bolt, their plump roots are more like fibrous wood than tender vegetables.

Once space is relinquished, tomato, eggplant and pepper plants might be the first vegetable plants to go back into the garden. Even if the weather gets cool for a while, it will not get cool enough for frost. Roots disperse as soon as they get into the ground. Warming weather accelerates growth above ground. Fruit develops through summer. (Fruits contain seed. True vegetables do not.)

Tomato, eggplant and pepper are popularly planted as seedlings because only a few plants of each are needed. Each plant probably costs more than a single package of seed (which contains enough seed to grow many more plants than are necessary), but are still not too expensive collectively. Seedlings get established and start growing more efficiently than germinating seed does.

Various melons and squash, including zucchini, can either be planted as seedlings or sown as seed. Their seeds germinate and grow so efficiently that seedlings probably do not have much advantage. However, their seedlings are relatively fragile to handle, so might be at a disadvantage. Seedlings might be practical for one or two plants; but seed might be best for several plants.

Bean and cucumber grow most efficiently from seed mainly because several or many of each plants are grown, and also because seedlings are somewhat sensitive to transplant. Onion and potato are popularly grown from onion or potato ‘sets’, or ‘seed’ onions or potatoes, which are merely juvenile vegetables that grow into productive plants. Onion can also be grown from seed.

Way Beyond Last Frost Date

90410thumbScheduling of gardening chores is as important now as it ever was. We plant warm season vegetables and annuals in time for spring and summer. We plant cool season vegetables and annuals for autumn and winter. We pick flowers as they bloom. We harvest fruits and vegetables as they ripen. We watch the seasons change on our calendars, as well as in the locally specific weather.

Yet, the one scheduling tool that we do not hear as much about as we did when agriculture was more common in the region is the ‘last frost date’. It refers to the average date of the last potentially damaging frost for a specific region. The last of such frosts might actually be earlier or later, but the last frost date remains a standardized time to plan particular procedures and planting around.

There are likely a few reasons why we do not talk about the last frost date much. The most relevant reason is likely the timing. Around here, the last frost date is sometime in January. It is earlier in some spots, and later in others, but it is sometime between January 1 and 30. It is simply too early to limit much of what we do in the garden in early spring, and is irrelevant to most winter chores.

It might seem to be just as irrelevant now, since the last frost was so long ago. Seed for warm season vegetables and annuals is sown as the weather gets warmer only because it would grow too slowly while the weather is too cool in winter, not because of a threat of frost. There really is quite a bit of time between the last frost and warm spring weather, while the weather is still rather cool.

However, pruning of plants that were damaged by frost should have been delayed at least until after the last frost date, and perhaps as late as spring. Although unsightly, damaged growth shelters inner growth from subsequent frost. Besides, premature pruning stimulates new growth that is more sensitive to subsequent frost. Most of such pruning is delayed until just after the last frost date.

If delayed longer, fresh new growth will show how far back damaged stems must get pruned.

Annuals Should Match The Weather

P80317Pulling out cool season annuals that are still somewhat colorful is never easy, even if they are already deteriorating. There is always the desire to stretch their season as late as possible until they succumb to warmer weather. Only a few can perform all year, or get cut back to hide below other taller plants until the weather gets cool enough in autumn for them to regenerate and bloom again.

Regardless of all the resistance, removing the annuals of a previous season relinquishes space for annuals that are appropriate to the next season, whether cool to warm season, or warm to cool season. Even if new annuals are initially wimpy relative to the older annuals that were removed, they should proliferate and bloom better than lingering unseasonable annuals would if not removed.

Timing is somewhat important. There is no point in removing cool season annuals too early if the weather is still too cool for warm season annuals. However, there is no point in planting too late either. Delayed planting only delays growth and bloom. Some warm season annuals, especially those grown from seed sown late in winter, prefer to get established while the weather is still cool.

French marigold is probably the most traditional warm season annual for bright yellow, orange and bronze. Lobelia contrasts excellently with rich blue and purple, and can also be purplish rose or white. Petunia can do even more with brighter and more variable colors. Cosmos provides pastel pinks and white on taller plants. Cockscomb colors rival those of marigold, and can also be red.

Pincushion flower, annual statice and zinnia are popularly enjoyed as bedding plants, and also work well individually, behind lower bedding plants, or in planters of mixed annuals or perennials. Verbena and moss rose cascade nicely from such mixed planters. Sadly, brightly colored and formerly popular busy Lizzie (impatiens) are either rare or unavailable because of a mold disease.

Nasturtium and alyssum are warm season annuals that are often grown through winter as well. Where they are allowed to naturalize and bloom throughout the year, deteriorating old plants might need to be groomed out as they get replaced by self sown plants. New nasturtium should be sown as seed, instead of planted as seedlings from cell packs. Alyssum grows well by either means.

What Bulbs Do After Bloom

90403thumbNarcissus, daffodil, freesia, snowdrop, snowflake, grape hyacinth, various iris and most other early spring blooming bulbs and bulb like plants should be perennials. We plant them with the hope that the will survive after bloom to bloom for another season, and perhaps for many seasons. Some should multiply to provide more bloom over the years. Bloom is just part of their annual cycle.

Lily, crocus, hyacinth, tulip, anemone and ranunculus are not nearly as likely to bloom more than one year for a variety of reasons. Some prefer more chill in winter. Some dislike the long and dry summers. Some survive as perennials, but do not bloom again. However, in some special situations, they also can bloom annually. After spring bulbs, there will be a different set of summer bulbs.

So, what happens after bloom? After exhausting much of their stored resources on production of bloom and foliage, bulbs try to recover and regenerate resources for the following season. Most work to replace their exhausted bulbs with comparable new bulbs. They need foliage to do this, but eventually shed their foliage as their new bulbs go dormant for the following autumn and winter.

Of course, they all do this at different rates. Some smaller bulbs are surprisingly efficient, and shed their foliage as soon as the weather gets warm later in spring. It is amazing that they can store up so much in such a minimal time. Other bulbs shed slowly, as their deteriorating foliage lingers for a few weeks into summer. Foliage of summer bulbs that bloom later is likely to linger until frost.

Because it is essential to the regenerative process, deteriorating foliage can not be cut back prematurely. It is not always easy to hide either. In mixed plantings, it might be obscured by ground cover or other plants. Alternatively, warm season annuals can be planted over the area. Some of us braid daffodil leaves, but others believe that braids draw attention to the deteriorating foliage.

Those of us who still dig and store and perhaps chill marginal bulbs, must wait for complete dormancy.

Pull Weeds Before They Seed

60323thumbSpring brings out the best and the worst in the garden. While warm season annuals and vegetables are getting established, so are a variety of weeds. Just like other annuals and perennials, they respond to the changing weather. Cool weather and moisture stratified their seed through winter. Warming moist soil prompts germination. Warm and sunny spring weather promts rapid growth.

There are all sorts of weeds. A few are big trees like bluegum eucalyptus and shamel ash. Some are substantial shrubbery, like privet and cotoneaster. Pampas grass and giant reed are big grassy perennials. The most familiar and prolific weeds are annuals or small perennials, like foxtail, burrclover, purslane, bindweed, sowthistle, pimpernel, spurge, crabgrass and Bermudagrass.

It is best to pull weeds as soon as they are big enough to grab onto. It will take more effort to pull them as they disperse their roots, and as the soil gets drier through spring. Unwanted shrubbery and tree weeds should be pulled like any other weed because they are likely to regenerate from roots if merely cut down. Once they recover and grow more, they will be much more difficult to pull.

Many small grassy weeds can be cut down low with a weed whacker, instead of pulled out completely. In some situations, low cut or mown weeds are better than bare soil. Some types of weeds will neither bloom nor disperse seed if mown. However, many types adapt to mowing by merely blooming and seeding lower. Dandelion and foxtail are notorious for their defiance to mowing.

Weeds are very efficient and creative with the dispersion of their seed. It is impossible to prevent seeds from coming into the garden from the outside. Yet, it is still best to inhibit the production and dispersion of seed from within the garden. Spurge and oxalis bloom and disperse seed in secret before they seem to be mature enough to bloom. Other weeds have taller or more prominent blooms that can be cut down before producing seed, even if the weeds are not actually removed completely.