Summer Is Not For Planting

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New plants are less reliant on irrigation if installed at the beginning of the rainy season.

Autumn is the time for planting. Cooling weather slows plants down so that they do not mind disruption so much. Increasing rain (hopefully) keeps the soil evenly moist while roots slowly disperse. The combination of cooling weather, increasing rain and shorter days keeps plants well hydrated so they can slowly ease into spring.

Why is this important now? Well, it probably is not important. It merely demonstrates why this is not the best time for planting. Only a few warm season annuals and vegetables get planted this time of year. Seeds for certain autumn vegetables get sown now. Otherwise, more substantial plants should wait until autumn if possible.

Mid summer in some ways is the opposite of autumn. While the weather is warm, plants are too active to be bothered. Even minor disruption can be stressful. Soil moisture provided by irrigation is often too irregular and unreliable for dispersion of many new roots. There is less time to recover from stress during shorter nights.

Smaller plants and seeds survive summer planting better than larger plants do. Seeds need to disperse all new roots anyway, so they  will adapt to what they get. They certainly need regular watering, but are quite talented at putting their roots wherever the moisture goes. With a bit more time, smaller plants will do the same.

Larger plants have more difficulty with the planting process because they need to disperse so many more roots to get established. When they get planted, all their roots are initially confined to the volume of media (potting soil) that they were grown in. They are susceptible to whatever happens within  that limited volume.
For example, a small plant in a four inch wide pot is initially confined to less than sixty-four cubic inches of soil. It can double its soil volume to one hundred forty-four cubic inches by merely dispersing roots less than one inch laterally. A tree in a 24-inch wide box needs to disperse roots ten inches laterally to do the same!
It would seem that drought tolerant plants would be less susceptible to the stress of planting in summer.

However, they are more sensitive because they are so reliant on extensive root dispersion. Until they disperse their roots, they actually need to be watered as frequently as other plants do.

Summer Vegetables Like Warming Weather

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Summer Vegetables Like Warming Weather

Tomato, pepper and eggplant plants should be out in the garden by now. They typically get planted only a few weeks after the last threat of frost, so that they can start to disperse their roots early. Growth above ground accelerates as the weather gets warmer. Fruit develops and ripens through summer.

These three types of vegetable plants get planted as seedlings for two main reasons. First, when they go into the garden, seedlings are bigger and more established than seeds that need to take time to grow are. Secondly, the cost of the few plants needed for an average garden is not much more than the cost of seeds.

Now, zucchini, melon and summer squash can be done either way. Not many plants are needed, so the expense of seedlings is minimal. However, seedlings are a bit more fragile than those of tomato, pepper and eggplant. Seeds grow so efficiently that they get established almost as readily as seedlings do, so are just as practical.

Regardless of how they get planted, the weather has been so odd this year that there has been only minimal advantage to planting seedlings and sowing seed on time. Tomato, pepper and eggplant plants that were planted early may not be much more mature than what could be planted now. Harvest will be delayed either way.

Bean, cucumber and corn all grow best from seed. Seedlings take more time to recover from transplant than seed take to germinate and grow. Besides, so many plants of each type are needed that seedlings would be expensive. A single package of seed is cheap and goes a long way, so is probably sufficient for an average garden.

Corn is one of those vegetables that produces on a rather tight schedule. Seed that gets sown at any particular time matures at the same rate, so that all the fruit finishes at about the same time. This is why corn gets sown in phases. If timed properly, a subsequent phase begins to produce as the preceding phase gets depleted.

Winter squash, including pumpkin, are similar to summer squash, although they are more tolerant of unusually cool spring weather. They too can either get planted as seedlings or sown as seed. They take their time to produce fruit that ripens by autumn, so have more time to catch up.

Crop Rotation For Home Gardens

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Pepper plants should get relocated annually.

Vegetable gardening is not permanent landscaping. With few exceptions, vegetable plants are annuals, like bedding plants. They do their respective jobs within only a few months. When finished, they relinquish their space to different vegetable plants of a different season. More of the same will be in season again in a few months. Crop rotation is something to consider when that happens.

Crop rotation is standard procedure for field crops involving several acres of the same variety of vegetable. Some crops grow on the same land for a few years. Some change annually. With few exceptions of big perennial vegetable plants, none stay in the same location for too long. Some fields go fallow for a season without production. Most simply produce a different type of vegetable.

Vegetables that grow for too long in the same soil eventually deplete some of the nutrients that they use most. Different types of vegetables deplete different types of nutrients. Crop rotation allows soil that was depleted by one type of vegetable to be used by another type that does not mind the depletion. While slowly depleted of a new set of nutrients, soil recovers from previous depletion.

For example, a sunny side of a fence is an ideal spot to grow pole beans. It is tempting to grow them there annually. However, they do not perform as well for a second season, and are likely to be scant for a third year. However, tomatoes appreciate what beans do to the soil, and do not miss what they took from it. After tomatoes take what they want for a season, beans are ready to return.

Crop rotation also helps to disrupt the proliferation of host-specific pathogens that overwinter in the soil and decomposing plant parts.

Generally, new vegetable plants should not be of the same family as vegetable plants that they replace in a particular location. Beans, squash, okra or corn should be happy where tomatoes grew last year. Peppers and eggplants are of the same plant family as tomatoes, so are likely to crave what the tomatoes already depleted. They are also susceptible to some of the same pathogens.

Planting Bare Root Stock Properly

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Bare root roses bloom next summer.

Most of the advantages of bare root stock are obvious. Bare root stock is less expensive and easier to work with in regard to installation and pruning to a desired form. What some of us may find difficult to understand is that it actually gets established into a new garden more efficiently than canned (potted) nursery stock does. As incredible as it seems, there are a few simple reasons why.

Instead of dispersing roots within the confinement of cans, bare root stock disperses roots directly an extensively into the soil into which it gets planted. Their initial deficiency of roots encourages them to do so quickly. Roots of canned stock must recover from confinement. Their new roots may be hesitant to leave the comfort of the extra rich medium in which their original roots developed.

The holes dug for planting bare root stock need not be much wider than the roots can be spread apart, and no deeper. If too deep, newly planted stock will sink as the loosened soil below settles. Grafted plants must not sink enough for their graft unions to be below grade. A cone formed of firmly pressed soil at the bottom of a planting hole can be useful for spreading roots out evenly over.

Rich soil needs no amendment. If compost is added to loosen dense soil, it should be as minimal as practical. Too much amendment will tempt roots to stay close rather than dispersing remotely. Fertilizer is not necessary immediately after planting. However, because the soil does not stay very cold here, and roots start growing before spring, mild fertilizer can be applied shortly afterward.

Finally, most bare root stock should be groomed and probably pruned after planting. Fruit trees are often sold with only minimal prior pruning. Superfluous stems function as packing material that buffers the ravages of transportation, and also provide more options for preliminary structural pruning. Aggressive pruning of plants that benefit from it concentrates resources for growth in spring.

Deodar Cedar Migration – Update

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Reassigned deodar cedars have adapted to their new landscape.

Reassignment is in season right now. The brief article about it that posted yesterday links to three other related articles. We have done quite a bit of it here, and intend to do a bit more for useful plants that happen to be in the wrong situations. It should be done before winter ends, to take advantage of both natural dormancy and cool winter rain that settles transplanted roots.

Most plants that get reassigned get dug from situations where they can not stay, and transplanted directly to where they will likely become assets to their respective landscapes. Those that do not get transplanted directly into other landscapes get canned and housed temporarily in the nursery. Some need to recover. Some must wait for landscapes that can accommodate them.

Some reassigned plants are feral descendants of exotic (non-native) species, that grew from self sown seed. Others were originally planted intentionally, but for one reason or a few, are no longer appropriate for their particular situations. Some are overgrown perennials that needed to be divided. On rare occasion, we encounter specimens of native species that get reassigned.

Deodar cedar that were reassigned slightly more than a year ago recovered from the process last spring and summer, so should grow this year as if nothing ever happened. Unfortunately, several were inadvertently killed when the roadside weeds and grasses that they grow amongst were cut down. In other areas, too many superfluous specimens survived, so must be culled.

Those that will be culled out need not go far. They can be plugged back to replace those that were mown down. The second process will be easier than the first. Superfluous specimens were reassigned because we expected nearly half to not survive the process. Except for those that were mown down, almost all survived. If not culled, they will get too crowded in just a few years.

There are plenty more where they came from. The four parent trees are prolific with their seedlings. We can not reassign all of them to other landscapes, and should not waste resources on canning specimens that will not likely be accommodated within any of our landscapes. I will likely can many of them, but not for here. They may become GREEN street trees in Los Angeles.

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The four reassigned deodar cedars in this small space are not easy to see in this picture.

If it seems as if the reassigned deodar cedars are too close to surrounding trees, it is only because the surrounding trees will be subordinated and eventually removed as the deodar cedars grow big enough to replace them. One is a dangerously disfigured sweetgum with roots that are displacing pavement above. Two others are disfigured and deteriorating California bay trees.

Reassignment

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African iris are happily rehomed.

African iris, Dietes bicolor, that I mentioned three weeks ago were finally installed into a new landscape. It may not be permanent. They may need to be relocated again if they happened to land where two of four birch will be installed as the landscape is slowly assembled before winter ends. The installation was done hastily before the last storm delivered a good dose of rain.

It could not be delayed any longer. These African iris had been divided and groomed so long before they were featured on the fourteenth of December that they were likely to succumb to rot or desiccation if installation was delayed any longer. They soaked in buckets of water for days at a time, and were then left to drain for days at a time so that they would not soak for too long.

I do not remember how many times I repeated the process. I knew it was getting risky. Surprisingly, by the time they were installed, only a few of the worst of the rhizomes were beginning to exhibit negligible indications of rot. Now that they are in moist but fluffy and well aerated soil, they can recover and begin to disperse new roots, even if they must be relocated again later.

If relocated again later, the process will be fast and direct. They will get dug and plugged within minutes. Compared to alternated soaking and draining for more than a month, it will be easy.

The formerly feral birch that will eventually be added to this landscape are also being reassigned. Of nine that were removed from another landscape in the neighborhood, five were already plugged directly into a landscape across the road. The other four were canned temporarily until we determine where they will fit into this new landscape. They will arrive before winter ends.

Lauristinus that formerly inhabited this area were already being reassigned as hedges in other landscapes before we planned to reassign extra African iris and feral birch to this landscape. A few got canned to replace any that do not survive the process. So far though, all have not only survived where they were reassigned, but were growing happily before the weather got cool.

Bare Plants With Bare Roots

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Dormant plants do not miss soil.

Knowing how colorfully bulbs will eventually bloom can initially make planting them disappointing, since there is nothing to see for all the effort. Planting bare root plants is not much more rewarding. The bare stems are a bit more proof of the effort, but will do nothing until they break dormancy in spring. Now that Christmas trees have vacated nurseries, bare root plants will be arriving, and will need to be planted before winter ends.

As the name implies, bare root plants have bare roots, without the soil they were grown in. Better equipped nurseries ‘heel in’ bare root plants in moist sand, which simply means that the roots get buried temporarily. When purchased, the plants get pulled from the sand and wrapped for the trip to their new home garden, where they get planted permanently into real soil.

Alternatively, bare root plants can be prepackaged in bags of moist sawdust. They only need to be removed from their packaging and sawdust before getting planted into the garden. Mail order plants, including plants purchased online, often get packaged even more simply, with a damp bag around the roots, maybe with a bit of gel or damp paper. The plants are safely dormant, so are not even aware of what is going on.

The main advantage of bare root plants is that they cost about a third of what typical nursery stock in heavier cans of media (soil) cost. Because they are so much less cumbersome, several bare root plants can be purchased at a time, and brought home in a small car without much effort. Since they lack the luxury of the soil they were grown in, they immediately disperse their roots directly into the surrounding soil.

Roots of bare root plants should be spread away from each other at planting. Soil amendment is nice, but should not be so copious that roots will not want to disperse outside of the amended soil. Even if rain is expected, newly planted bare root plants should initially get soaked so that soil settles around the roots. Grafted plants should be planted with the graft union above grade.

Fruit trees such as apricot, cherry, plum, prune, peach, nectarine, almond, apple and pear, as well as roses, are the most popular of bare root plants. Flowering crabapple, flowering cherry, poplar, willow, lilac, forsythia, wisteria and grape are also available.

Bare Root Season Has Begun

00108thumbBefore all the Christmas trees were sold and relinquished their space, the smaller types of bare root stock started arriving in local nurseries. Blackberries, raspberries, blueberries, gooseberries, currants, grapes, strawberries, rhubarb and asparagus, may have been available for a while. More substantial bare root stock, such as roses, fruit trees and ornamentals, may already be arriving.

Bare root stock is known as such simply because its roots are bare. It gets dug as dormancy begins in autumn, and separated from the soil it grew in. It remains dormant as it gets transported to nurseries, and then to home gardens where it ultimately gets planted. It is completely unaware of the otherwise unsurvivable processes until it wakes up to resume growth in a new home in spring.

The roots of some of the smaller bare root plants and roses, as well as some fruit trees, are bagged in damp sawdust. Most bare root fruit trees, as well as some of the smaller plants, are merely heeled-in to damp sand, and upon purchase, pulled from the sand and bagged without packing material. Roots can soak in water for a few days prior to planting, but will not survive dry exposure.

There are several advantages to bare root stock. It is significantly less expensive than canned (potted) stock. It is also easier to get from a nursery and into the home garden. Branch structure can develop directly in a garden, rather than adapt from how it developed earlier in a nursery. New roots disperse directly into the soil, so need not recover from former confinement within a can (pot).

The more popular bare root fruit trees that are now becoming available are stone fruits, pomme fruits, persimmons, figs, mulberries and walnuts. Stone fruits are those of the genus Prunus, which contain single large seeds known as stones. These include apricots, cherries, plums, prunes, peaches, nectarines, almonds and their weird hybrids. Apples, pears, and quinces are pomme fruits.

(Almonds are nuts that are actually stones of leathery fruits that dry and separate from the stones as hulls.)

Growing Problem

P91221KRecycling plant material is practical and gratifying. We do quite a bit of it here. Back in September, I briefly wrote about recycling laurustinus that was removed from an area that was about to be landscaped, and relocated to other sites where it can grow into functional informal hedges. We were able to use something that was a problem in one location as an asset somewhere else.

We will be doing more of this sort of recycling now that the rainy season has started. Right now, the plants that need to be removed are as dormant as they get, so do not mind getting dug as much as they would have while they were still active. Rain helps settle them in at their new locations. A few get canned and stocked into the nursery, to be planted into new landscapes later.

Some of what gets recycled was intentionally installed in the past, but for one reason or another, became inappropriate for a particular site. For example, I will soon be relocating agapanthus that performed well for many years, but eventually became too shaded by growing trees nearby. Forsythia that has already been relocated was too big and awkward for its confined space.

Many plants that get recycled were not intentionally planted, but happened to grow wild in situations where they can not stay. Some are native. Some are descendents of desirable exotics. The laurustinus that I mentioned above are such an example. Just yesterday, I relocated a few naturalized but superfluous birches from an established landscape to an unlandscaped area.

We certainly do not recycle everything that can be recycled. Many plants, both native and naturalized exotic, are just too problematic. Fleabane that I wrote about yesterday is marginal.

Sweetgum happens to be one of those trees that we probably should not recycle. They are splendidly colorful in autumn, and particularly spectacular amongst the deep green redwoods. The problems are that the now overgrown trees here are developing serious structural deficiency, and producing an overwhelming abundance of messy and potentially hazardous maces (fruits).

Nonetheless, I found and canned these four rooted sweetgum watersprouts. They were growing from roots of one of several big and very problematic sweetgums that got removed last year. If they get planted here, they and their associated problems will be located outside of refined landscapes. In the future, thy can drop maces and limbs in the forest without bothering anyone.

Reassignment

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There is quite a bit of open space in some parts of the landscapes. It is not as if the landscapes are lacking much. There just happens to be a few spots where a bit more could be added. This expanse of healthy English ivy was already appealing, but lacked interest.

There is also quite a bit of spare plants out and about in the landscapes. It is not as if there is anything wrong with spare plants. There just happens to be too many of them. These cannas got overgrown and crowded within their original colony in another landscape, so needed to be divided and thinned out.

We are not a so-called ‘landscape’ company, which profits from the removal of some plants, and the installation of others. There is no incentive to dispose of as much vegetation as we could bill a client for. Nor is there any incentive to install as many new and expensive plants as we could fit into any available space. It is not a ‘business’.

To the contrary, it is in our own best interest to exploit resources that are already available to us. For example, when we thinned out these crowded cannas from one situation, we reassigned them to other situations where they could grow and become assets to their new landscapes. Also, viburnums that were removed from one site were reassigned as hedges in other situations.

We will be doing more of this sort of reassignment now that the weather is cooler and rainier, and the plants that will get relocated are dormant. Carpet roses that must be removed from the boundary of a playground because they are too thorny will be relocated to a broad roadside, where they can grow wild. They will be replaced with lily-of-the-Nile that is crowded elsewhere.