Timing Soil Inputs

Getting your soil right for planting can often leave many growers scratching their heads in confusion. There are numerous options available on the market and knowing when to add inputs to your soil is crucial.

Let’s explore the “WHENs” of soil inputs:

When to test the soil

Before you plant a single seed or buy a product, you need to know what’s going on beneath the surface. A soil test can tell you what your soil lacks or has too much of. Getting soil tests in the fall after harvest or early spring allows you to correct imbalances way ahead of planting time. Testing early gives you time to understand your soil’s nutrient profile, pH, and organic matter content.

For cannabis and other nutrient-hungry crops, regular testing (at least once per season) helps guide mid-season inputs, especially before flowering. Other growers may only need to get their soil tested every three years.

When to add fertilizers and amendments

Whether you want the greenest lawn in the neighborhood or a lush garden this year, adding fertilizers and other soil amendments can make all the difference. Once you have your soil test results back, you’ll be able to make the right fertilizer choices for your particular soil and plants.

You can apply slow-releasing fertilizers in the fall or spring to provide consistent nutrients over time. If you notice that your plants are weak and yellowing, you may need to give them a boost with a fast-acting fertilizer. This can be done every 3-4 weeks during the growing season. However, be cautious when applying fast-acting fertilizers, as they can cause damage and even kill your plants.

Apply any additional soil amendments, such as compost, manure, rock dust, or other minerals, based on your soil test results. You can do this before you start planting or top dress throughout the growing season as needed.

When to add microbial inoculants

There are a number of microbial inoculants you can add to your soil from biofertilizers to biostimulants. However, it’s always best to apply them at the beginning of the growing season so the microbials have enough time to colonize the root zone early and form symbiotic relationships as roots begin to grow.

For transplants, it’s ideal to apply inoculants directly to the root ball or into the planting hole, ensuring close contact with the roots. In systems where the soil has been tilled or disturbed, you’ll want to reapply your inoculants to reestablish the colonies. Growers should also consider reapplying inoculants after using fungicides or sterilizing agents that may kill or reduce the microbes in or on the soil.

In cannabis cultivation, microbial inoculants are particularly valuable during the cloning and transplanting phases. Mycorrhizal fungi can significantly enhance phosphorus uptake and improve stress tolerance, both of which are critical for strong vegetative growth and successful flowering later on. Because these organisms thrive in moist, aerated soils, timing applications with irrigation can also help them establish more effectively.

When to add Beneficial Nematodes

Pests under the soil are often the most challenging. Luckily for growers, they can add an exceptional underground ally-beneficial nematodes-to support their operations. Beneficial nematodes should be applied in when the soil temperatures are between 42°F – 95°F. The warmer the soil, the more active the nematodes, and the greater the protection and results. Also, avoid applying them during dry spells or in full sunlight, as UV rays and dehydration can cause them to die quickly. Water the soil before and after application to help them establish.

Knowing when to apply the nematodes depends on what pest you are trying to control. For example, if you're targeting fungus gnat larvae in greenhouse cannabis or vegetable production, it's best to apply nematodes early in the season or just after transplanting, just before adult gnats start laying eggs. If you're managing root-knot nematodes or root weevils in perennial systems, applications are most effective in late spring when larvae are actively feeding near the root zone. In turfgrass or pasture settings, nematodes targeting white grubs should be applied in late summer or early fall, when young larvae are close to the soil surface and most vulnerable.

Each pest has a specific life cycle stage that’s most susceptible to nematode predation. Proper timing ensures that beneficial nematodes find their targets before they cause significant damage, and before they retreat deeper into the soil where nematodes are less effective.

Final Thoughts

Treat your soil right, and you’ll reap huge benefits in the end. Improving the soil won’t happen overnight, as great soil health starts long before you plant your first seed. By testing your soil early, timing inputs to match plant growth stages, and using biology-based inputs like microbes and nematodes, you set your crop up for long-term success.

So, don’t just feed your soil. Observe and listen to it.  It might just tell you exactly what you need.

 

Japanese Beetles

Japanese beetles are the bane of many growers. These voracious pests feed on over 300 plant species, skeletonizing leaves and damaging flowers, fruits, and crops. Their ability to thrive in diverse environments makes them a persistent problem for growers across the United States.

These beetles are an invasive species that originally came to the US in 1916. Since then, Japanese beetles have spread south and west, covering most of the eastern United States and into the Midwest. Today, Japanese beetles continue to expand their range, causing significant damage to both home gardens and commercial agriculture.

Life cycle and biology

Japanese beetles are small beetles with a metallic green and copper color. They will often raise their hind legs in a defensive position to deter predators.

Females will lay their eggs in the soil in late summer, and the eggs will hatch into white, C-shaped grubs. These white grubs eat grass roots and can cause damage to lawns and turf. The grubs will overwinter and continue feeding when the weather warms up in the spring.

As the grubs grow and mature, they will pupate in the soil and emerge as adults. The adults then get to feeding and mating. The beetles skeletonize the leaves of plants, meaning they eat the leaf tissue between the veins.  

Preferred plants

Over 300 plants are on the menu for Japanese beetles. However, they do show a strong preference for certain plants. Some of their favorites include:

• Roses (Rosa spp.)
• Grapevines (Vitis spp.)
• Maple Trees (Acer spp.)
• Apple Trees (Malus spp.)
• Linden Trees (Tilia spp.)
• Corn, soybeans, and other row crops

They also attack ornamental flowers, fruit trees, and garden vegetables. While they feed on a wide variety of plants, they tend to avoid lilacs, boxwoods, and certain conifers.

Methods of control

Since Japanese beetles spend most of their time in the soil and their adult forms are highly mobile, it’s often best to target them in their grub stage.

While trapping has become a popular tactic, this can often bring more adults to the trap and they can spill over onto your vulnerable plants.

Some of the best methods for controlling them include:

Beneficial Nematodes – These microscopic worms target beetle grubs in the soil, killing them before they mature into adults. Check out our Hb NemaSeek nematodes and Sr NemAttack nematodes for grub control.

Milky Spore (Paenibacillus popilliae) – This naturally occurring bacterium infects and kills Japanese beetle grubs, but takes time to establish in the soil. It’s offered in both powder and granule forms.

Need Seed Meal – This neem tree derivative acts as both a soil amendment and a natural pesticide. When applied to lawns and garden beds, it disrupts the feeding and development of Japanese beetle grubs, reducing their survival rates. It also improves soil health, making it a dual-purpose solution.

Suppose you want to target adult beetles that are damaging your plants. In that case, you’ll want to adopt a more integrated pest management approach, combining both cultural and physical strategies with natural insecticide treatments.

Physical control - Removing beetles by hand in the early morning and dropping them into soapy water can help reduce populations in small gardens.

Row Covers – Using fine mesh netting can protect high-value plants during peak feeding periods.

Organic and Natural Insecticides – Using natural insecticides can help control Japanese beetle populations while minimizing harm to beneficial insects and the environment. Some of the best options include:

• Kaolin Clay – This fine clay powder forms a protective barrier on plant leaves, making them less attractive to Japanese beetles. It doesn’t kill the beetles but discourages feeding and egg-laying. Apply it early in the season before beetles become abundant.
• Pyrethrins – Derived from chrysanthemum flowers, pyrethrins are fast-acting contact insecticides that target adult beetles. They work by disrupting the nervous system, leading to paralysis and death. Pyrethrin sprays are best applied in the evening to minimize the impact on pollinators.
• 
  Azadirachtin(Neem Extract) – A key compound found in neem oil, azadirachtin disrupts the feeding and reproductive cycles of Japanese beetles. It acts as both a repellent and an insect growth regulator, preventing larvae from maturing into adults. Look for neem-based sprays with high azadirachtin content for the best results.
  

For effective control, apply these natural insecticides as soon as beetles first appear and reapply after rainfall. Combining these treatments with cultural controls and biological solutions offers the most effective long-term management strategy.

Japanese beetles are a persistent and destructive pest, but with the right management strategies, you can protect your plants. A combination of early intervention, natural predators, and selective treatments can keep their numbers in check. By targeting both the adult beetles and their soil-dwelling grubs, you can break their life cycle and minimize damage year after year.

 

New Tools for Greenhouse Growers to Battle Pests

Managing pests and diseases in greenhouses requires the right systems, expertise, and tools to stay ahead. Pests can be relentless, and the biggest troublemakers are often the smallest ones, like aphids, whiteflies, mites, mealybugs, and thrips. Fortunately, new bioinsecticides are changing the game. These innovations not only help control pests effectively but also support sustainable growing practices, reducing reliance on synthetic chemicals. Let’s dive into three powerful solutions that can give greenhouse growers the upper hand against these persistent invaders.

EpiShield: A Potent Essential Oil Blend

BioWorks has developed EpiShield, a plant-based miticide and insecticide formulated with peppermint and clove oil. Designed for both indoor and outdoor use, it effectively controls aphids, thrips, whiteflies, and mites, some of the most stubborn pests in greenhouse environments.

One of EpiShield’s biggest advantages is its high concentration, allowing growers to apply ten times less product than traditional horticultural oils while still achieving exceptional results. Unlike other oil-based treatments, it won’t burn leaves, making it a safer option for sensitive plants. This makes it especially useful for spot treatments on high-risk crops, where precision is key.

EpiShield is also a great addition to Integrated Pest Management (IPM) programs. Because of its unique formulation, it works well alongside other pest control methods, giving growers flexibility in their approach. With fewer application restrictions and a reduced risk of plant damage, EpiShield is a smart, effective choice for growers looking to tackle pests without compromising plant health.

BioCeres EC: Harnessing the Power of Beneficial Fungi

Another exciting innovation comes from Anatis with BioCeres EC, a bioinsecticide derived from the fungus Beauveria bassiana. This beneficial fungus is a natural predator of soft-bodied insects. The product either coats the insect exoskeleton with spores that eventually penetrate the insect body, or the insect consumes the spores, which then develop inside the pest. The pest is then killed after about 5-7 days. 

BioCeres EC is a liquid emulsifiable concentrate that can be applied to the soil or leaves to control both insects within the soil and those feeding above ground. It’s effective for egg, nymphal, and adult stages of life, giving you a robust tool for managing aphids, whiteflies, psyllids, thrips, and true bugs like spotted lanternflies. 

One of BioCeres EC's biggest benefits is that it’s OMRI-listed, making it an excellent option for organic growers. It’s also tank-mixable with other pesticides and foliar products, giving growers the flexibility to use it in combination with other treatments. Since Beauveria bassiana has no known resistance issues, BioCeres EC remains a long-term, sustainable tool for pest management in greenhouse settings.

LALGUARD M52 OD and LALGUARD M52 GR

Last on our list is another mycoinsecticide, or fungal-based insecticide, that provides an effective, natural solution for controlling pests in greenhouse environments. It comes in two formulations: LALGUARD M52 OD (Oil Dispersion), a liquid formulation for foliar application, and LALGUARD M52 GR (Granular), designed for soil-dwelling pests. Both formulations use the beneficial fungus Metarhizium brunneum, which naturally infects and kills a variety of insect pests.

The two distinct formulations allow for distinct applications. LALGUARD M52 OD is perfect for foliar pests. The spores adhere to the exoskeleton of the targeted pest and penetrate through it. Eventually, the fungus begins colonizing the insect’s body and eventually kills it. Because it’s an oil-based product, it has better coverage and dispersion among plants, ensuring it comes into contact with more pests.On the other hand, LALGUARD M52 GR is designed for soil-dwelling pests, including root aphids and fungus gnats. Since the granules release the fungal spores into the soil, they offer long-lasting pest control without frequent reapplications. This makes it a particularly useful tool for greenhouse growers dealing with pests that damage root systems and hinder plant growth.

 Smarter Pest Management for Greenhouse Growers

Greenhouse pest control doesn’t have to rely on synthetic chemicals. EpiShield, BioCeres EC, and LALGUARD M52 provide effective, environmentally friendly alternatives that help growers control pests while maintaining sustainability.

Each of these bioinsecticides offers a unique advantage. Whether it’s EpiShield’s essential oil-based protection, BioCeresEC’s powerful fungal infection method, or LALGUARD M52’s versatility in targeting both foliar and soil pests. By integrating these products into their pest management strategies, greenhouse growers can reduce pest populations, prevent resistance issues, and maintain healthy, thriving crops. 

How to Keep Your Poinsettias All Year

Christmas, as we all know, is a winter holiday. Yet in spite of its season, it has a surprising amount of plant life associated with it. 

Christmas trees make sense—after all, pine trees retain their needles throughout the winter. European mistletoe also blooms in winter, which led to it being featured in Christmas pageantry. In reality, mistletoe is a hemi-parasitic plant. It can photosynthesize, but it prefers to latch on to tree branches and steal water and nutrients from a tree. Not the best example of the Christmas spirit. 

This article will focus on a lesser known, yet still popular, plant associated with Christmas: the poinsettia. Unlike Christmas trees and mistletoe, many families wish to keep these poinsettias around past Christmas but are frustrated when they end up dying. Let’s figure out how to keep these guys alive until the next holiday season, shall we? 

If you’re looking for a simple answer as to why your poinsettias are dying, overwatering is the main culprit. Watering a poinsettia like you would a shrub or a flowerbed will kill them. You also need to understand that poinsettias are not going to stay red year-round. With that said, let’s take a closer look at the poinsettia. 

Poinsettias

Poinsettias are found in Central America, covering swaths of Mexico and peeking into Guatemala. Wild poinsettias look much different than the cultivated breeds you can purchase at your local garden center or hardware store during the holidays, but they still keep the flower’s distinctive red coloring.  

So, what do we do to keep a poinsettia alive and healthy for next Christmas? Truthfully, they are tricky plants to manage. There’s a reason why so many poinsettias are bought each winter. Even if you keep the plant alive for a year, there’s no guarantee that the poinsettia’s iconic red color will appear for the next Christmas. Still, it is possible to keep a poinsettia blooming for many consecutive Christmases. Let’s break things down step by step. 

 Once the New Year begins, fertilize your poinsettia to prolong its bloom. 

• After this initial fertilization, reapply fertilizer every 4 weeks. 

You’ll also want to make sure you’re keeping an eye on potential pests. 

• Whiteflies have a nasty habit of finding their way into poinsettia pots. 
• While using a biological control method such as green lacewings is a great way to keep whiteflies under control, most poinsettias are kept indoors, making this method of pest control significantly less appealing. 
• Instead, try an organic pest control method such as Agro Pest. 

You should be watering your poinsettia rarely! 

• To prevent overwatering, wait until the soil is dry, then wait a couple of extra days before watering. 
• If you’re watering more than once a week, you are overwatering. 
• Once March arrives, prune your poinsettia until it is no more than 8 inches tall to encourage new growth. 
• You can move your poinsettia outside for the summer, but you’ll need to stop applying fertilizer in August to prepare the plant for its dormant period. 
• Take your poinsettia back inside and into a controlled growing environment once September comes to an end. 

 

Poinsettias are photoperiodic, meaning they need long nights to trigger blooming. 

• This blooming is what causes the deep red color to emerge. 
• Once you’ve moved your poinsettia back inside, it will need 14 hours of complete darkness each night for about 8-10 weeks. 
• Do this by placing the plant in a dark closet or covering it with a box. 
• Even brief exposure to light at this time will prevent a poinsettia from blooming for Christmas. 
• Finally, during the day, return the plant to bright, indirect light. Continue this routine until the bracts (the official name for the red-colored leaves) begin to show color, usually around early December.

 

If everything has been done correctly, your bright red leaves will return as you’re putting the Christmas tree back up. If your leaves do not turn red, don’t feel too bad. Poinsettias are notoriously finicky, and you can always try again next year. 

- Robin @ ARBICO Organics 

3 Ways to Garden During the Winter

Not everyone has a greenhouse. We get it. Greenhouses require an upfront investment, can raise your utility bill each month, and there are a lot of decisions that need to be made, so it’s easy to get choice paralysis. Still, those of us who live in the colder parts of the USA (the parts that get snow and have to deal with winter) recognize that growing outside is no longer feasible once November rolls around. While having a state-of-the-art climate-controlled greenhouse alleviates this issue, there are additional ways to grow in cold weather. Cold frames, hoop houses, covers, and other garden accessories allow dedicated growers to mind their gardens through the winter months at minimal cost.

 

Cold Frames 

Cold frames are a form of greenhouse, though they’re much less high tech than a modern greenhouse. In fact, a cold frame doesn’t even need electricity to keep your plants warm. Instead, a cold frame possesses a transparent lid made from glass, plastic, or polycarbonate. This lid focuses light onto the plants, warming the inside of the cold frame, creating a microclimate, and increasing the amount of sunlight your plants receive. Still, cold frames do have their limitations. It’s difficult to truly overwinter a plant using a cold frame. Instead, cold frames extend the growing season. When you use a cold frame, you can harvest plants later and plant seeds for spring earlier. While the air inside your cold frame will be warm, the soil will still gradually freeze. You can slow down the freezing of your soil by adding hay, peat moss, or woodchips to your soil. 

 

Dark, leafy greens do well in cold frames. You’ll be able to harvest spinach, cabbage, and kale well into winter with a cold frame. You’ll also find success with root vegetables like potatoes and carrots. Once the weather gets warmer, simply put the cold frame lid into storage and you’ll be left with an ordinary gardening bed. 

 

Hoop Houses

Hoop Houses with Frost Covers

Hoop houses offer a more substantial level of protection than cold frames, which allows the avid grower to cultivate a wider range of crops throughout the winter. Like cold frames, hoop houses are also relatively low cost, though they are noticeably more expensive than cold frames. They consist of flexible hoops, typically made of PVC or metal then covered with a durable plastic sheeting. Unlike cold frames, which typically have soil at the bottom, hoop houses are more commonly used with raised-bed gardens. If you’re looking to overwinter a large number of plants, hoop houses tend to scale better than cold frames. 

 

The vegetables you overwinter in a hoop house are similar to those that thrive in cold frames, so think along the lines of lettuces and radishes. 

 

Frost Covers

Unlike cold frames and hoop houses, frost covers are best used as a temporary solution. If you’re looking to seriously extend your growing season, invest in a hoop house or cold frame. In fact, the plastic sheeting found on the outside of a hoop house is very similar to the tarp that comprises a frost cover. A frost cover is exactly what it sounds like. It’s a sort of blanket that you can lay down over plants to protect them from frost. This can be handy if you have a weird cold snap in early October or early May, but it’s not something that will sustain you through an entire winter. 

 

Stay Cozy and Keep Growing! - Robin @ARBICO Organics