Meeting Halfway On Citrus Grow-Out Houses

Here is a good example of a pole and cable structure recently built at the Whitmore Farm near Leesburg, FL. Photo by Peter Chaires

Photo by Peter Chaires

It is evident that growers are impacted disproportionately by HLB. There are a myriad of factors at play, some of which are understood — many of which are not. Rootstock, location, soil amendments, soil pH, nutrition, Asian citrus psyllid (ACP) control, water quality, and other factors vary from grove to grove. Despite the variables, one thing is certain: Florida’s citrus industry will rapidly be relegated to boutique status unless new trees are planted and brought into production.

Growers are focused on reaching production and positive cash flow as early as possible. Return on investment is the fuel that drives this engine. Fruit quality and fruit quantity are both part of this equation, but it all starts with the tree. Growers continue to consider new and innovative ways of accelerating tree performance and minimizing time needed to reach the first viable harvest. Several growers recently discussed their desire to increase the average size and trunk caliper of trees going to the field. They suspect larger tree size combined with aggressive ACP control and nutrition will enable them to stay in the game until better tools are available.

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The challenge is that nursery capacity remains somewhat constrained. Nurseries need their square footage to maintain product flow and meet orders. Leaving trees in the nursery until larger caliper is achieved is an unlikely option for most nurseries and would not be financially feasible for either party. Young trees must be protected from infection during grow-out. This presents a range of challenges. One option being considered is the construction of low-cost grow-out houses at grove locations. Such structures would serve as halfway houses where additional size can be achieved before movement to the field. Pole and cable structures can be constructed (depending on design) from $2.35 to $4.00 per square foot. Those seeking a positive pressure environment for maximum protection from ACP have the option of inflatable houses with vertical support fans in the $6 per square foot range.

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The idea of halfway houses has something in common with every other novel approach: It has its supporters and detractors. I reached out to nurseries and growers for comments. Here are some of the thoughts gathered:
I fail to see the benefit for my operation. The trees are very small when I receive them, but I am achieving much better growth on small citripot trees than the old bare root trees. I have a special fertigation and care program for my new young trees. Within a year, I am ahead of the larger bare root trees. I am profitable by year three. Having a halfway house would delay having to spend money on systemic insecticides, but I don’t see this as a major benefit. Screenhouses may be beneficial if the grower is having no success with new plantings. But if this is the case, it may be a caretaking and grove management issue as much as it is a disease problem. If so, I don’t see planting a larger tree resolving the issue.
I am very interested. I have a good ACP control program and am making progress with nutritionals. Larger caliper trees added into this mix may put me in a better position.
• Several commented on the need for more information on the optimal size tree for resets and solid block plantings. If the optimal size tree is something that cannot be achieved at the nursery, they would consider the investment in a structure. It is an economic question. The fact that growers want a 5½-inch potted tree for resets, but can manage a smaller tree for solid plantings, does suggest that management plans are a factor. This is a good place for guidance from the research community. Some growers are interested in the concept of a halfway house, but need more information before investing.
I have no interest in the concept of a halfway house for my trees. We are growing citripot trees to six feet tall in 18 months — even near metro areas. Anyone who is not hustling their trees along to a similar degree is behind the eight ball. The reality is that if you can’t keep a row of healed-in trees next to your pumphouse greening free, you’re in trouble. There are too many points on the data curve that suggest we are going to have to produce in a greening-free environment if we are to compete with fruit quality acceptable for fresh or processed. The industry needs to quit grasping at cheap fixes and admit that many of us have made a tragic mistake in thinking that we can live with greening. The infection is too deep for a Band-Aid. Growers need to change their mental paradigm or be part of the war of attrition.
Extra time in a halfway house also increases the likelihood that a therapy or other HLB management tool will be available when I am ready to plant.

Intel From Nurseries

I want to do whatever I can to support my growers. If they can’t remain profitable, I am out of business. However, I have limited space and am reluctant to expand right now. If they need larger trees and are willing to build a structure, I can offer advice on care of the trees.
I have concern that growers are ill-equipped to care for containerized trees in screen. This requires a level of expertise and commitment that is different from what growers are doing in the field. If container trees are moved to a screenhouse in good condition and then decline, the grower may look to the nursery as a cause. For me, my obligation would end when the trees leave my nursery.
Nurseries have had to develop a level of expertise in growing container trees in screen. The way that we grow trees today compared to 10 years ago is night and day. The same level of new thinking and ingenuity is needed to grow small trees in the field. We simply can’t do it the way we always have. When I visit customers with specialized care programs for resets and solid plantings — I see trees that are outperforming the larger trees I used to sell them. I suggest growers visit other operations that are having success with new plantings and adjust their practices before considering a halfway house. Where the halfway house may have the most merit is in areas where there are many small patchwork groves near residential areas and the bad-neighbor effect.
FNGLA’s Citrus Nursery Division has three seminars per year to explore new methods for containerized indoor production. If growers are interested in exploring the halfway house concept, they should consider membership so they get the most out of their investment.
Growers must understand that material cannot be sold from these structures. These would be for personal use only.
I have several concerns about this concept. This may encourage black market trees. Also, growers may be more hesitant to adapt new grove management practices, thinking the larger tree gives them a head start without it. When I produced bare root trees, I sold them at a caliper of 3/8 of an inch to 1/2 inch. Today, I sell citripot trees from pencil size to just under 3/8 of an inch and it grows faster and more consistently. I can show you 2-year-old trees that went to the field with a pencil sized caliper that are nine feet tall with 1/2 a box of fruit on them. It’s all about tree care.

Whether grower or nursery owner, the question of halfway houses relates back to grove management and current success rates in the field. With more financial data and information on optimal new tree caliper, growers will push a pencil and make decisions. Close communication between nursery and grower is essential. Nurseries have some expertise in this area and may be able to help those growers interested in building structures to maximize the investment. We will continue to monitor this issue and provide periodic updates.

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