Receiving New Plants
Most new spring bedding plants enter our ornamental greenhouses as plugs, liners, rooted or unrooted cuttings. Unfortunately, insect or pathogen issues experienced at the supplier can slip through their best efforts to deliver clean product, and we may start our new crop with built in disadvantages The best way to avoid these problems is to develop a proactive approach that isolates and treats all new plant material before it enters production.
One possible strategy would be to implement a protocol that utilizes biologicals for these early treatments. Beneficial insects or biocontrol agents (BCAs), microbial insecticides and fungicides are very effective at this stage of the crop. Since they are naturally derived products, microbials reduce the possibility of pesticide resistance. There are many advantages to using microbial products, including short reentry intervals, good plant safety, and they require minimal personal protective equipment (PPE), allowing transplanting to continue on a timely basis.
Most of the microbial products work well with BCAs, and together they will provide control while plants are staged for transplanting. There are several species of predators that thrive in the dense canopy of plug and liner trays that will hunt thrips, aphid, spider mite, fungus gnat, and whitefly. Plants that are treated early can be inoculated with live colonies of microbials and BCA predators that will protect them through the transplanting process, right up to the first treatments they receive in the production area.
Figure 1: Lacewing (Chrysoperla carnae) Larvae (photo credit: Bioline)
Isolate and Scout
Always inspect new plant material upon arrival for signs of insects, disease, and other unusual growth. Even if the plants look clean upon first inspection, it is recommended to quarantine and observe plants in an isolated area, separate from the rest of production. Quarantine areas can be created from plastic sheeting or other physical barriers. Developing a proactive quarantine protocol is a strategic investment in the long-term health of your greenhouse.
Dipping Incoming Plant Material
Plant dips are an effective method of applying approved pesticides to unrooted cuttings (URCs), rooted cuttings, plugs and liners. This method of application is often used to reduce or eliminate insect, mite, and disease issues on incoming plant material. Most commonly, plant dips include a complete submergence into a diluted pesticide solution. This method of application provides maximum coverage, which is especially good for dealing with pests that hide in leaf axils and under the foliage.
Due to the absence of root materials, unrooted cuttings can be easily dipped in a number of approved solutions, including botanical oils and soaps; even some sanitation products have dip labeling.
Rooted cuttings, plugs and liners benefit when completely submerged in a solution of microbial pesticides. A combination of both a microbial insecticide and a microbial fungicide has proven to be effective. Bioinsecticides can remove a large percentage of pest insects from inside the canopy. Biofungicides will not eliminate or cure existing pathogen issues, but they will inoculate clean young plants to prevent further infestation. Many growers will add a nematode species, S. feltiae to aid in the elimination of fungus gnat and thrips larvae to the mix.
Figure 2. Dipping poinsettia cuttings enclosed between two mesh trays (Images courtesy of BioWorks)
Growers have developed a variety of creative ways to dip plant material quickly and efficiently. Mesh bags and other screens can be used to quickly drain excess solution after dunking. Entire flats can be submerged into large containers. Products approved for dipping have instructions on the label dictating the drip treatment duration time and rates. When in doubt, always perform small-scale trials before treating an entire crop. Once treated, plant material should be placed in an area away from direct sunlight and in moderate air temperature conditions to dry. Please remember that everyone involved in the dipping process is considered an “applicator/handler”. It is important to note that the REI and PPE from the product labels must be followed even when dipping. Please reach out to GGSPro or your local Griffin Sales Representative to request our Plant Dip Bulletin for more information on appropriately labeled products and rates.
Holding for Transplant
Rooted and unrooted cuttings can now be prepared for “sticking.” As plug trays and liners are returned to the quarantine area, BCAs can be released almost as soon as the biopesticides have dried. See chart below for a few helpful organisms that target the most common pests of young plants. Note that they are often useful against more than one pest species.
Table 1: Organisms for targeting common pests
Start Clean to Stay Clean
It goes without saying that a weed-free free environment and good sanitation practices are key to a positive, trouble-free start to the growing season. GGSPro has comprehensive, step by step sanitation guides for hard surfaces, irrigation systems, and reusing pots/contains/trays for your benefit available upon request. By implementing a proactive strategy to isolate and treat incoming plant material, growers can reduce the number of potential problems that they will have to face early in the season. By utilizing bio-friendly microbial products as a preventative measure, they can save conventional chemistry for later in the season.
Note, not all products are registered in all states. Some pesticides are restricted use in some states or regions and not others. It is the responsibility of the applicator to read and follow all label directions, remembering that labels may change. Other products may be safe and effective. Rates, application methods, and edible status are detailed in our GGSPro Insecticide & Fungicide Guides. Griffin also offers the 5th Edition GGSPro Technical Reference Guide in both English and now Spanish versions. This valuable resource outlines a wide range of pest control options and information on pollinator safety, BCA’s, scouting, weed management, plant lighting, nutrition, water quality and more!
Most new spring bedding plants enter our ornamental greenhouses as plugs, liners, rooted or unrooted cuttings. Unfortunately, insect or pathogen issues experienced at the supplier can slip through their best efforts to deliver clean product, and we may start our new crop with built in disadvantages The best way to avoid these problems is to develop a proactive approach that isolates and treats all new plant material before it enters production.
One possible strategy would be to implement a protocol that utilizes biologicals for these early treatments. Beneficial insects or biocontrol agents (BCAs), microbial insecticides and fungicides are very effective at this stage of the crop. Since they are naturally derived products, microbials reduce the possibility of pesticide resistance. There are many advantages to using microbial products, including short reentry intervals, good plant safety, and they require minimal personal protective equipment (PPE), allowing transplanting to continue on a timely basis.
Most of the microbial products work well with BCAs, and together they will provide control while plants are staged for transplanting. There are several species of predators that thrive in the dense canopy of plug and liner trays that will hunt thrips, aphid, spider mite, fungus gnat, and whitefly. Plants that are treated early can be inoculated with live colonies of microbials and BCA predators that will protect them through the transplanting process, right up to the first treatments they receive in the production area.
Figure 1: Lacewing (Chrysoperla carnae) Larvae (photo credit: Bioline)
Isolate and Scout
Always inspect new plant material upon arrival for signs of insects, disease, and other unusual growth. Even if the plants look clean upon first inspection, it is recommended to quarantine and observe plants in an isolated area, separate from the rest of production. Quarantine areas can be created from plastic sheeting or other physical barriers. Developing a proactive quarantine protocol is a strategic investment in the long-term health of your greenhouse.
Dipping Incoming Plant Material
Plant dips are an effective method of applying approved pesticides to unrooted cuttings (URCs), rooted cuttings, plugs and liners. This method of application is often used to reduce or eliminate insect, mite, and disease issues on incoming plant material. Most commonly, plant dips include a complete submergence into a diluted pesticide solution. This method of application provides maximum coverage, which is especially good for dealing with pests that hide in leaf axils and under the foliage.
Due to the absence of root materials, unrooted cuttings can be easily dipped in a number of approved solutions, including botanical oils and soaps; even some sanitation products have dip labeling.
Rooted cuttings, plugs and liners benefit when completely submerged in a solution of microbial pesticides. A combination of both a microbial insecticide and a microbial fungicide has proven to be effective. Bioinsecticides can remove a large percentage of pest insects from inside the canopy. Biofungicides will not eliminate or cure existing pathogen issues, but they will inoculate clean young plants to prevent further infestation. Many growers will add a nematode species, S. feltiae to aid in the elimination of fungus gnat and thrips larvae to the mix.
Figure 2. Dipping poinsettia cuttings enclosed between two mesh trays (Images courtesy of BioWorks)
Growers have developed a variety of creative ways to dip plant material quickly and efficiently. Mesh bags and other screens can be used to quickly drain excess solution after dunking. Entire flats can be submerged into large containers. Products approved for dipping have instructions on the label dictating the drip treatment duration time and rates. When in doubt, always perform small-scale trials before treating an entire crop. Once treated, plant material should be placed in an area away from direct sunlight and in moderate air temperature conditions to dry. Please remember that everyone involved in the dipping process is considered an “applicator/handler”. It is important to note that the REI and PPE from the product labels must be followed even when dipping. Please reach out to GGSPro or your local Griffin Sales Representative to request our Plant Dip Bulletin for more information on appropriately labeled products and rates.
Holding for Transplant
Rooted and unrooted cuttings can now be prepared for “sticking.” As plug trays and liners are returned to the quarantine area, BCAs can be released almost as soon as the biopesticides have dried. See chart below for a few helpful organisms that target the most common pests of young plants. Note that they are often useful against more than one pest species.
| Beneficial | Pests Targeted |
|---|---|
| Stratiolaelaps scimitus | Soil dwelling mite, fungus gnat larvae and thrips pupae |
| Dalotia coriaria | Soil dwelling rove beetle, fungus gnat larvae and thrips pupae |
| Steinernema feltiae | Beneficial nematode, fungus gnat larvae and thrips pupae |
| Amblyseius cucumeris | Predatory mite, thrips 1st instar and some broad mite |
| Amblyseius andersoni | Predatory mite, thrips 1 |
| Amblyseius swirskii | Thrips 1st instar, whitefly larvae and some spider mite |
| Chrysoperla spp. | Lacewing larvae, aphid, thrips all life stages, caterpillar eggs, some spider mite eggs |
| Phytoseiulus persimilis | Predatory mite, spider mite all life stages |
Start Clean to Stay Clean
It goes without saying that a weed-free free environment and good sanitation practices are key to a positive, trouble-free start to the growing season. GGSPro has comprehensive, step by step sanitation guides for hard surfaces, irrigation systems, and reusing pots/contains/trays for your benefit available upon request. By implementing a proactive strategy to isolate and treat incoming plant material, growers can reduce the number of potential problems that they will have to face early in the season. By utilizing bio-friendly microbial products as a preventative measure, they can save conventional chemistry for later in the season.
| Item Name | Approved For | Rate/Comments | Item Number |
|---|---|---|---|
| Actinovate SP | Cutting or Bare-rooted transplants. | 6-18 oz/50 gal; let soak up to 3 hours. | 71-1117 |
| Companion Maxx | Bareroot transplants. Plug dip, plant or trays. | 4-8 fl oz/100 gal, 1-5 min. 4-8 fl oz/100 gal, 30 seconds. | 166072 |
| Companion WP | Cuttings or root dip, basal end or bare roots individually or in bunches. | 0.5-1.5 lb/gal water, 5-10 seconds. | 71-1372A2 |
| Guarda | Pre-plant soil borne diseases. | 1 qt/10 gal prior transplanting. | 71-1610 |
| KleenGrow | Preplant fungal & bacterial on seed, bulb and corms. | 0.15-1.5 fl oz/gal for 30 seconds. | 74-21125 |
| Obtego | Cutting, bare root, crown dip, bulbs. | Dip undiluted into powder or at 0.25-2.0 lb/gal water prior to planting. | 71-2105 |
| OxiPhos | Seeds, seedlings, bulbs cutting. | 64 fl oz/50 gal; immerse, remove, drain, do not rinse. | 71-2350 |
| RootShield Plus WP | Dip for food crops, cuttings, bareroot, ornamentals, etc. | 0.25-1.5 lb/20 gal. | 71-27921 |
| RootShield WP | Cuttings, bulbs, transplants. | 0.25-3 lb/20 gal; trees 0.2-2.5 lb/5 gal. | 71-2789 |
| Stargus | Soil borne diseases. | 1-4 qt/100 gal prior transplant. | 71-2950 |
| Triathlon BA | Cutting or root dip. | 1-2 pt/gal; immerse roots or basal end for 5-10 seconds. | 71-3040 |
| ZeroTol 2.0 | Pre-plant dip for root diseases in ornamentals in greenhouses. Bareroot nursery stock. | 64 oz/50 gal; immerse, drain, do not rinse. 1 ¼ fl oz per gal; dip until wet. | 71-35501 |
| BotaniGard 22 WP | Cuttings, URC to rooted plants. | WP – ¼-½ oz per gal water. | 70-12521 |
| EpiShield | Cuttings Dip, URC. Foliage (above-ground portions) of rooted cuttings. | 0.09 fl oz (2.7mL)/gal for 10-30 seconds. | 70-1545 |
| LalGuard M52 OD | Cuttings, URC to rooted plants. | ½-1 fl oz/gal; thoroughly wet all areas to be treated. | 70-2291 |
| M-Pede | 2EE label -Whitefly, mites (not NY) as pre-plant dip to ornamentals, Foliage (above-ground portions) of rooted cuttings. | 0.25-0.5% v/v to transplants. Tank mixes at a 0.5% v/v to transplants. | 75-10262 |
| Velifer | Cuttings, URC to rooted plants. | 7-13 fl oz per 100 gal; allow URC to dry before sticking, rooted can be planted immediately. | 70-9540 |
Note, not all products are registered in all states. Some pesticides are restricted use in some states or regions and not others. It is the responsibility of the applicator to read and follow all label directions, remembering that labels may change. Other products may be safe and effective. Rates, application methods, and edible status are detailed in our GGSPro Insecticide & Fungicide Guides. Griffin also offers the 5th Edition GGSPro Technical Reference Guide in both English and now Spanish versions. This valuable resource outlines a wide range of pest control options and information on pollinator safety, BCA’s, scouting, weed management, plant lighting, nutrition, water quality and more!