Expert: Long Island Gardener - 4/5/2007

Question
QUESTION: Hi Long Island Gardener,

I had these 3 wonderful boxes of the Wave petunias mixed with the multiflora type petunias.  They all flowered once and were an amazing sight.  Now unfortunately they've begun to wilt and die.  On closer examination there are these small white insects that look like rice grains, but about 1-2mm in length.  And the leaves look like they haven't been watered in days.  The plants get about 4-5 hours of direct sun from noon to evening.  Now, some branches are dead and the others have flowers on them.  Did read somewhere about some virus, as some leaves have light green streaks on them.  It just breaks my heart to see them wilt like this.  HELP!!
ANSWER: No problem, Alex.  Those little white insects can be dispatched easily and overnight with a few Ladybugs.  Can you buy those in your town?  Get a bag.  Sprinkle around the petunias and watch.

Of course, you did not use any pesticides this year on your plants because you know how bad those are.  So your Ladybugs can live a long and productive life this summer dining on Aphids and other Evil Insects in your Garden.  Correct?

Ladybugs.  These are truly amazing creatures.  You'll be amazed.

Now, those Petunias would be much happier if they were getting more sun.  Can you move them to a brighter, sunnier place?  Because 4-5 hours of Sun is not Full Sun.  It's more like Part Sun, at best.  And Petunias are Full Sun plants.  Any choices here?

Viruses do strike.  But you have these little bugs and that sun problem.  Viruses are not on your short list.

The leaves are wilting because the roots are not getting enough water to them before the insects zap the sap.  Ladybugs will fix that.

Let them recover.  Then a few days later, when they are in Full Sun, pinch them -- prune off the top leaves right down the middle of the stem with a scissors -- and you'll inspire new branches and bottom growth.  Although I don't usually recommend fertilizer for Petunias, since they have been through so much, a single dose of fertilizer would do them some good.  Not too much.  Just once.

And for your nerves, take 2 aspirin and call me in the morning.  After the Ladybugs have been deployed.

Any questions?

---------- FOLLOW-UP ----------

QUESTION: Hey Long Island Gardener,
bought the ladybugs and have deployed the troops.  Now gonna wait for a few days before the other instructions.

However, was planning on buying a few more varieties and the person at the plant nursery told me that it wasn't worth it as their season was ending and they would die.  But I have read somewhere online that Petunias if grown in a container and kept away from frost (I live in tropical weather -- never dips below 77F (24C)) they were all year round.  Just wanted your opinion on this.

Thanx again for the other advice -- sitting with a magnifying glass and can already see the effect.

Answer
Petunias in the tropix... this is something I can truly say I have NOT been there, NOT done that.  It is a whole new ballgame.  Glad you mentioned that.

My first reaction is, Why would anyone want to grow Petunias when they can grow all that other stuff?

But of course if you can, why not?

Those Petunias are so bright, they light up the soil everywhere they grow.  White is my favorite.  The 'Wave' hybrid was introduced from Japan ca. 1990 boasting some very specific features.  They proved so popular nationally that the developer followed with trellis-climbing 'Tidal Wave'; mounding 'Easy Wave' for borders; and double-flowered 'Double Wave'; plus the low, spreading 'original' Wave.  They share outstanding recovery properties, flower resilience and disease resistance plus all the best features of traditional Petunia hybrids.

But it threw me at first when you said that the Petunia 'season was ending and they would die'.  Here in Zone 7, the snow has barely melted and it was 33 degrees F this morning.  Petunias Season is months away.  But that's here.

But in the world that I live in, Petunias are annuals.  They'll bloom through November, when everything else is dormant; at that point, Petunia season is over and they're gone, never to return.

Technically, these will bloom indefinitely so long as they are alive.  Because technically, Petunias are tender perennials with South American tropical genes.  They love sun, they love heat.  So if Petunia 'season' is finished, at some point in the future it would make sense that it would begin again.  So you should be able to assume that since these are -- techncially -- perennials, they would grow forever.

And therein lies the key.

How do you keep something this vigorously 'healthy'?

Perennials have On and Off buttons, with a rest period in between.  Petunias being Zone 9/10 plants, they are going to need a rest.  Which after what those bugs are putting them through anyone would need.  I'd need one too.

Sp I don't agree that these will die.  But as they age, they won't be as spry and energetic.  Plus, remember, these are hybrids with genes for intensity and power, not for perennial longevity.  When the breeders scooped up wild Petunias down in South America to obtain new genetic material, they were not thinking, 'Let's sell Petunias that have a long perennial life.'  They were thinking $$$$$ and Yen Yen Yen.  They had to think in those terms because no one would buy Petunias just because they came with a guarantee to bloom in perpetuity in Zones 9 and 10.  People expect things of their Petunias: They should be cheap, easy and very pretty.  They had to work from there.  The marketing was a stroke of genius; these are the fast-food high-quality immensely popular best sellers of the garden world.  They're easy to grow, photogenic and cheap.  You also want them to live forever?

OK, they'll do that.  But they will be blooming little old ladies and little old men, spent and weary.  The grower did not price them to bloom on the level you are asking for.

But why not try?

What I think you should do is take cuttings from your Wave Petunias -- after they recover from what's bugging them -- root those and grow new plants that will branch and bloom like new.  Which they would be.  Possibly this is a patent infringement but I don't think anyone will call the police.  Just imagine the headlines.  You'd be world famous.

Alternately, you can try resting them, and wait for daylength and temperatures to trigger them out of dormancy.  Keep them 'pinched' -- pruned of top growth to encourage branching -- and don't fertilize until they seem to be 'waking up'.  Don't overwater; Petunia roots are susceptible to rotting and they need air.  But when they dry out, water again.  Read the 'Petunia Plant Pointers' (http://www.wave-rave.com/How_To_Grow.aspx) for a little more guidance.  They need a slow release fertilizer AFTER the rest period, which should last probably around 2 months, just guessing here.  If you love these that much, you'll enjoy this little hobby of yours.

The poor Ladybugs will be hungry.  If you know someone with Roses you can drop off a few and see if they'll skip pesticides this year and use Ladybugs to eliminate the Aphids looking for tender new growth.

That's the whole story of your Petunias in the Tropics.

You should try Orchids this year.  Let me know if you want some tips.  Thanks for writing and keep me posted.  I could learn something here.