LOOK OUT! Here comes the Spider Man! (Oops. I mean Mites. Spider mites. Sorry; way less exciting).

spider mite-GillianFWeekly-mum producers have seen higher-than-normal spider mite levels coming in on cuttings from the U.S. recently.  This might impact seasonal potted-mum growers as well.

Here’s some tips and tricks on two spotted spider mite control within a chrysanthemum IPM program.

Continue reading “LOOK OUT! Here comes the Spider Man! (Oops. I mean Mites. Spider mites. Sorry; way less exciting).”

It’s “B” Season! Watch for Botrytis, Broad Mite and Burn.

Honeybee 2Although native bees and honeybees may just be starting to gather strength and are beginning to fly outside, other “B’s” have been of growing concern in the greenhouse for some time now.

These include common spring bedding crop problems like Botrytis cinera (aka grey mold), Broad mites, and leaf burn (from a variety of causes).

Keep reading for tips on how to manage these issues during this time of year.

Continue reading “It’s “B” Season! Watch for Botrytis, Broad Mite and Burn.”

Using Beleaf (flonicamid) as a drench: benefits and (potential) drawbacks.

gi_0_beleafGiven that it’s the season for pest problems like aphids on spring crops, I’d like to remind everyone of an important new pest management tool we have at our disposal.

Thanks to the hard work of Cary Gates at Flowers Canada Growers, and OMAFRA’s Jim Chaput, Beleaf (flonicamid) can now be used as a drench on greenhouse-grown ornamentals and cut flowers.

Read on for more details regarding the expanded label and potential phytoxicity issues.

Continue reading “Using Beleaf (flonicamid) as a drench: benefits and (potential) drawbacks.”

Spring crops that are “magnets”for certain pests.

aphid_cali_UMAssYou know the old rhyme: “April showers bring May flowers, but what do May flowers bring? Aphids“. Or sometimes it seems that way, anyways, with Spring bedding crops.

To help guide your pest management program this year, our  friends (superiors?) over at Michigan State Extension have released a handy  list of which crops are likely to attract which pests.  Keep reading for more info.

Continue reading “Spring crops that are “magnets”for certain pests.”

Supplemental Lighting Options for Bedding Plant Seedling Production

Happy spring!  With the season in full swing, we know that growers are busy this month.  I read an interesting article on the effects of supplemental LED lighting in bedding plants this week, and I’ve summarized it here with the key messages at the bottom of this post.  It seems like an appropriate article for the season, especially if you are starting to think ahead to how you might improve production for the 2017 spring season.

Much of the LED lighting research done in ornamental plants has focused on finding the best wavelengths for plant production.  This can vary based on the plant being grown, and the qualities desired.  Before we dive into the study, let’s review some of the reasons why you might consider LED lights from a plant production standpoint. Continue reading “Supplemental Lighting Options for Bedding Plant Seedling Production”

Managing Million Bells

By Sarah Jandricic and Chevonne Carlow

It’s that time of year again, when baskets of Million Bells (Calibrachoa) are going up in the greenhouse.  Here’s how to deal with and prevent some of their most common issues.

Fe def calibrachoa


Iron deficiency in Calibrachoa.  The resulting yellowing can look similar to symptoms caused by black root rot or nitrogen deficiency.

From a nutritional standpoint, the best thing you can is keep the pH of your calibrachoa in its ideal range; between 5.5 and 6.0.  A pH higher than this can inhibit nutrient uptake, especially micronutrients such as iron. 

 

Iron deficiency can be difficult to distinguish from other issues (like Black Root Rot – see below), but typically leads to yellowing of new growth.  Leaves may only show chlorosis between the veins, or it may be spread throughout the leaf.  This is different from nitrogen deficiency where yellowing occurs in the oldest leaves. If iron deficiency occurs, adding a chelated form of iron is best for uptake.

Yellowed plant growth (yellow circle) and dead plugs (orange circle) on a plug tray of Callibrachoa.
Yellowed plant growth (yellow circle) and dead plugs (orange circle) on a plug tray of Callibrachoa from black root rot.

Million bells are also highly susceptible to Black Root Rot (Thielaviopsis) – I’ve seen this take out a good chunk of a crop.  Symptoms include:

  • Stunting of foliage and roots
  • Plants in a tray will have uneven heights
  • black areas on roots
  • yellowing of leaves

Prevention is worth a pound of cure with this disease, as it is difficult to eradicate once established.  Important steps to take include:

  • Proper Sanitation. To avoid an issue with Black Root Rot year after year, immediately dispose of  diseased plants, limit water splashing, and sanitize benches, floors and used pots/plug trays.  Always physically wash surfaces  with a cleaner to remove organic matter, then follow up with a  disinfectant such as KleenGrow (ammonium chloride compound).
  • Consider prophylactic applications of fungicides on plug trays.  Products include Senator (thiophanate-methyl) or Medallion (fludioxonil). Preventative applications are an especially good idea if you’ve issues in the past. Adding bio-fungicides containing Trichoderma harzianum (e.g. Rootshield, Trianum) may also help
  • Lowering your pH. This disease is significantly inhibited by a lower pH – between 5.0 and 5.5.
  • Manage fungus gnats and shoreflies, since these insects can spread Black Root Rot between plants. Treatments include nematodes, Hypoaspsis mites , or applications of Dimiln (diflubenzuron) or Citation (cyromazine).

If already established, rotated applications of Senator and Medallion may limit Black Root Rot, but are unlikely to cure it.

aphid_cali_UMAss

Aphids tend to be found on flowers and new growth of Calibrachoa.

Lastly, Million Bells are highly attractive to aphids.  With baskets hung up in the greenhouse, they can be “out of sight, out of mind”, but  regular monitoring is needed to prevent large aphid outbreaks.  Place sticky cards directly in baskets, and routinely check plant material for aphid cast skins and honeydew.

Once aphids are detected (and they will be!), applications of  Beleaf (flonicamid), Enstar (kinoprene) or Endeavor (pymetrozine) will usually take care of them.  However, be aware that all of these insecticides take around 4-5 days to start causing aphid death.