1 | What is the role of mycorrhizae in plant nutrition?

Outside the root, mycorrhizal fungi develop into the soil by extending their mycelium (hyphal network) and prospecting for nutrients far from the plant. The nutrients are relocated and delivered to the root. They are exchanged with the host plant through dedicated exchange structures. In this trade, the plant obtains mainly water, macronutrients and micronutrients from the mycorrhizal fungi. In return the fungal symbiont receives organic carbon compounds (photosynthates), in the form of lipids and sugars produced by its photosynthetic host. These photosynthates are then transferred and used in the growing margins of the mycelium and developing reproductive structures such as carpophores and spores.

The main outcome of this complex and finely tuned symbiotic interaction, and ultimately the role that mycorrhizae play, is to greatly improve the ability of the plants to gather and utilize water and nutrients, from the surrounding soil or substrate.

2 | Why should growers consider using mycorrhizal fungi to improve plant nutrition?

LC: This mycorrhizal symbiosis directly contributes to plant nutrient availability and utilization throughout the plant’s entire life cycle. Mycorrhizal fungi are capable of accessing nutrient pools in the soil/substrate that are inaccessible to plant’s roots by solubilizing these tightly-bound nutrients and delivering them to the plant. Due to this increased nutrient efficiency, mycorrhized plants need significantly lower amounts of readily-available fertilizers compared to non-mycorrhized ones, which reduces the economic impact of plant nutrition on the overall costs of plant production.

3 | How does mycorrhizal inoculation affect different types of plants?

LC: Mycorrhizal fungi adapted and evolved to interact with different plant species over more than 400 million years. In doing so they differentiated in specific and particular types of mycorrhizae, among which the most important are the Endomycorrhizae or Arbuscular mycorrhizal fungi (AMF), which interact with many flowering ornamentals, vegetables and farm crops, and the Ectomycorrhizae, which interact mainly with hardwoods and conifers. The most efficient mycorrhizal inocula (such as the MycoApply® professional brand produced by Mycorrhizal Applications) have different fungal species either of Endo- and/or Ectomycorrhizal fungi, capable of interacting simultaneously with multiple plants also belonging to different species. This diversity improves the plants’ environmental conditions, giving them an advantage.

More specifically, mycorrhized plants present faster growth and better resistance to stresses compared to non-mycorrhized ones. This might be the critical factor for a successful establishment of plants in a new environment, such as a production container, and for faster and improved plant production in controlled conditions.

4 | What do growers need to know about applying mycorrhizae?

LC: Although mycorrhizal interactions improve plants’ nutrient availability and utilization and reduces the toxic effects of certain nutrients’ excesses, the presence of high concentrations of phosphorous (P) is known to be detrimental for the establishment of mycorrhizae. Therefore, over-fertilization might hamper the capability of the plant to benefit from a mycorrhizal inoculum. Another key factor to establish mycorrhizae is to carefully apply the inoculum as close to the plant’s growing roots as possible, to facilitate the contact with the active ingredient (mycorrhizal fungi) and speed up the development of the symbiotic interaction.

5 | Aside from plant nutrition, are there other unforeseen benefits of mycorrhizal inoculation?

LC: Several studies and field trials have shown that plants’ resistance to abiotic stresses (including drought, salinity, pH, and heavy metals) is greatly increased. Another indirect beneficial effect of mycorrhizae that has been documented in the scientific literature is an improved ability of the plant’s defense mechanisms to be less impacted by pest attacks. This increase in immune response is considered more of an indirect benefit, and may be attributed to the increased overall vitality of mycorrhized plants in general.

For more: mycorrhizae.com

1 | Why is consistency a prime objective for Lambert?

When you have consistency in the mix, you will make the life of the grower a lot easier. It will help a lot if you receive a mix that will drain and react the same each time. A new crop will require almost the same watering and fertilization frequency because of the drainage of the mix, air space and porosity. You have enough to adjust with the weather each year. You don’t really want to deal with the mix on top of that. You can rely on this component and concentrate your efforts to adjust the other components that change from season to season.

2 | How does Lambert keep its mixes consistent?

If you can have standard processes to prepare the field and harvest the raw product, that will help you at the second step, screening. Our screening system permits almost endless possibilities. We can achieve almost every peat grade that could be asked for by the customer and we can replicate it each time. That flexibility is very important. For the customer, it’s important to receive a mix that will have the same physical properties from batch to batch, season after season.

After you screen the peat and produce your mix, it’s important to have good quality control at the end. We apply vigorous processes to ensure that all specifications are met before allowing production to be transferred to the transportation department for delivery. In any case, if one specification is not met, production will be on hold and not allowed to leave our yard. When you let the product go, you are responsible and you have to make sure the customer receives a product in total compliance with the specification they expect.

3 | What are some examples of quality control measures Lambert has taken?

Consider the EcoPeat series of mixes, one of Lambert’s newer products. It’s made with a natural fiber from the peat bog used to produce mixes with an exceptional ratio of air porosity and water holding capacity. We took many years to test EcoPeat Mixes (EPM), so when we released them and started marketing them, we were really comfortable with that product. Now, it’s a really good seller for us. The consistency of the components is the key of that mix line. At the beginning it was not so easy to always have the same grade. We needed to make a lot of adjustments. But when you can achieve exactly the same grade from batch to batch, whether it’s -25 degrees outside or +25 degrees, you are very proud of it.

We always take the necessary time to make the adjustments and test it before putting a new product on the market. We have growers willing to do a half-acre or a couple tables in the greenhouse with a new suggestion we bring to them and trial it in “real life” conditions.

4 | How do you handle growers who have different needs?

We receive a lot of requests for fine-tuning options. It’s not always a big difference, but when you can make an adjustment to help the customer to get exactly what they’re looking for, whether it’s lower pH or a mix with no N-P-K, customers really appreciate that.

Most nursery growers for example are working with EPM-40, the High Porosity Mix. It’s perlite-free and includes Canadian sphagnum peat moss and EcoPeat. It’s ideal for large containers, perennials and nursery crops.

The same principles also apply for germination mixes. You need good seed contact between the peat moss and the seed, but you also need air space. You cannot afford to have big sticks or big chunks in the mix because they will not fill the trays correctly. But at the same time, you also do not want only fines. You have to make the adjustments to make sure you have a mix that allows good seed contact and at the same time will not clog the machinery, or clog cells in the trays. Consistency is important whether you sell a truckload or just a couple pallets because every customer is important.

For more: www.lambertpeatmoss.com

Perennials are a profitable crop. And to keep those sales up, Josiah Raymer, general manager at Emerald Coast Growers, advises how make a few production adjustments to keep your perennial crops looking their best.

1 | When should I pot perennial liners to overwinter for next year?

Early fall is a great time to pot liners to start bulking up for spring sales. This works well for perennial plants such as Phlox and Astilbe and ornamental grasses such as Pennisetum and Miscanthus.

If you’re wanting early spring sales of warm-weather grasses, you’ll need to perform some well-timed bulking. Grasses such as Miscanthus, Panicum, Andropogon and Schizachyrium will respond well to bulking in summer and fall months. Put up liners in early to mid-summer, allowing enough time to finish by fall. June to July is a good window. Then, let them get a good dormancy period over the winter, which promotes good vigor coming out of dormancy.

2 | Do I plant different perennials at different times?

Be careful not to pot up day-length sensitive plants too late. The shortening days and cooler temperatures trigger dormancy. Remember, tender perennials don’t bulk and overwinter well.

One way to control crops with a strong photoperiod response is by getting them potted early enough in the summer that they will be finished by September or early October. Crops with a weaker photoperiod response, such as perennial grasses Pennisetum and Miscanthus, can be potted later in summer, as they will continue to grow for an additional four to eight weeks depending on day length and temperature.

If you have potting schedules or other constraints that force you to do all of your potting at once, changing your liner size can also help control finish times. Starting with a larger liner can shorten finish times and get your crops finished on time.

3 | Should I overwinter my plants in cold frames or outside?

Either will work. Use a perennial cloth to provide protection from frigid winter in northern climates. Farther south you may be able to get away with placing plants pot tight for protection. If you’re using cold frames, be sure to vent on warmer days, or plants may overheat.

4 | How do I adjust my fertility program for overwintering?

You want to cut back as you’re nearing the dormancy period. The most flexible option is liquid feeding, but you can also schedule a slow-release fertilizer that will run out as fall begins. Choose a fertilizer with lower nitrogen as you’re moving toward dormancy — remember you want to encourage a shift from lush new growth to energy storage in the roots.

As you near the end of overwintering, and before your crops come out of dormancy, it’s important to get pH and electrical conductivity (EC) readings. You may need an application of liquid feed fertilizer, or you may need to leach your pots if your EC is low or high respectively.

5 | How do I prepare my leftover pots for overwintering?

Start by removing old foliage just before winter, but after plants go dormant. The less organic matter to deal with in spring, the better, and you won’t have to work through new growth to cut back old foliage. Both perennials and ornamental grasses can overwinter next to new production.

If plants aren’t root bound, fertilize them when they break dormancy in the spring to have them ready for early sales. If they are root bound, shift material into a larger size in the fall or the spring. Base your decision to shift them in the fall or wait until spring on whether they have enough time to root out in their new pots prior to dormancy.

A preventive fungicide drench can help reduce root rot issues in areas with wet winters.

For more: www.ecgrowers.com

Research indicates that shrubs in mixed containers have piqued the interest of consumers. Alec Charais, marketing and communications manager at Bailey, describes how growers can create some dynamic, big-ticket products that will boost profits for both the producer and the retailer.

1 | What makes using shrubs in decorative containers appealing for the end consumer, and what should a grower know before implementing a production program that incorporates them in the mix?

When it comes to container gardening and gardening in general, people are looking for plants that are an extension of their own personal style. For some it is a more traditional look, whereas others are trending toward more modern styling. Container gardening offers that ability to customize the experience from the get-go. Growers and retailers have the opportunity to inspire consumers with ready-made containers that feature more than just typical herbaceous plants. Our own research has told us that people are open to using shrubs in containers, yet it isn’t top of mind when in store due to lack of inspiration. Finally, shrubs in containers are easier to take care of, making them more appealing from that aspect.

2 | Are there certain varieties that work best, and what should someone keep in mind when creating a combination recipe?

The beautiful thing about it is that really, anything can work. Certainly, there are some items that are more desirable than others. Flowering shrubs with a long bloom period and compact habit such as BloomStruck^® or Summer Crush^® from Endless Summer® Hydrangeas make for excellent candidates because they look great as monocultures or in combination with other annual and perennial color. Foliage shrubs such as Little Devil^™ Ninebark and Straight Talk^™ Privet are also excellent choices due to their clean lines and almost architectural look. Southern plants such as Distylium (Vintage Jade, Coppertone^™, etc.) and Gardenia (Double Mint, Sweet Star^®) varieties are also excellent choices thanks to their clean, glossy, evergreen foliage making them look great in both home and commercial applications.

3 | In terms of finishing time and the care involved during production, what are some key cultural considerations (pruning, PGRs, fertility, etc.) for growers?

There are a number of ways for growers to produce decorative containers that feature ornamental shrubs. For example, Hydrangea macrophylla forces extremely well for Mother’s Day sales by taking dormant finished product early spring and heating to force into flower within 8-10 weeks with very little in the way of growth regulators. This is especially true for growers in the Midwest and Northern parts of the country. In warmer climates, much of the planting can be done early in season so the plants can have an opportunity to set new roots before shipping. Some growers and retailers prefer to bring in finished product and then simply drop it into a decorative container or wrap for quick retail presentation, which is certainly fine, as well.

4 | What should retailers do to keep them looking good on the shelf? How about consumers once they get them home?

Like all retail products, the first rule is to sell the inventory so you don’t have to care for it long term. That said, their care is really no different and is likely easier than with annual combos since shrubs don’t require constant deadheading and nutrition. If the grower has incorporated a slow-release fertilizer in the media, then infrequent water-soluble nutrition is more than enough to supplement their requirements. The same would be said for the consumer once they have them home.

5 | From a pricing perspective, what about the cost/price/value equation? Are their price points to keep in mind?

This is where many growers get hung up. Due to the long-term nature of woody plant production as compared to bedding plants, liner selection is the most important influence on both quality and profitability. This allows flexibility for the grower to simply bring material in when they are ready for it, minimizing the amount of time caring for it. Some growers may opt to use potted liners or bare root if their facilities are set up for it, which can reduce their up-front costs provided they have the production capacity for this. 

For more: www.baileynurseries.com