Found a mealy -- safe to soak right now?

[Steve Johnson]

Okay, I just found a stinkin' mealy on my Copiapoa hypogaea today. Watered it last night, so if I water with Imidacloprid again tonight, that'll add an extra day of moisture before the mix dries out. I don't think the plant would be susceptible to rot since it's still warm enough, but I'd like to get a second opinion. If someone can respond ASAP, I'd really appreciate it.

Thanks!

[Saxicola]

The benefit of stopping a mealy bug infestation before it gets big is greater than the risk of watering two days in a row. By the way, did you see that it might rain upwards of 4 days next week?

[Steve Johnson]

The benefit of stopping a mealy bug infestation before it gets big is greater than the risk of watering two days in a row. By the way, did you see that it might rain upwards of 4 days next week?

I concur and yes I did. Re. the concurrence, I appreciate your confirmation on giving the hypogaea a soil soak tonight. Spraying with IPA has proven to be both safe and effective in a pinch, so I'll do that on the surrounding plants. However, the hypogaea has too many nooks and crannies for mealies to hide in, and in this case a systemic is the only way for any peace of mind there. So glad we have nice October weather here in SoCal! Speaking of...

Well, maybe not so nice this week -- but I'm prepared. Last winter I rigged up a plastic rain shelter over my shade cloth enclosure. Only problem was that I kept it up from November until the end of March. Didn't count on the fact that constant UV exposure turned the plastic brittle, and the only thing that saved me from some soakers in March was a whole bunch of gorilla tape. Back to the drawing board I went, and I redesigned a much better one that goes up when it's needed, then comes down after the rain is over. Here's what my new rain shelter looks like when I put it to the test back in April:

Rain_shelter04252012_small.jpg (159.6 KiB) Viewed 518 times

The main part is a single piece going front, top, and back. The side flaps attach with velcro, and the bottom corners of the shelter are tied down with nylon twine. If I take off the side flaps, the plant bench gets cross-ventilation so I don't have to take the whole shelter down when there's rain that keeps coming and going a lot. However, it takes only 5-10 minutes for deployment and tear-down, and that's fine since I think my cacti would appreciate it better if they're not confined under plastic for months on end over the fall/winter season. And when it's needed, that new and improved shelter keeps the cacti totally dry, dry, dry!

By the way, it occured to me that I should really call this a portable greenhouse instead of just a rain shelter. When the plastic covers the shade cloth enclosure it'll provide some additional heat to the plants. I haven't taken actual temperatures under it, but my feeling is that it should raise daytime temps by at least 5 degrees. My 10-day forecast is for 68/59 on Tuesday, 66/58 on Wednesday and Thursday, 69/59 on Friday, then warming up to the low 80s at the end of next weekend. Hence it being a portable greenhouse -- depending on forecast changes, I'll put it up Monday night and take it back down Friday night. So it's not just about keeping the rain off, and if my theory is correct the warming assistance should prevent the cacti from interrupting their October growth over those cool days. Now let's see if it works!

Thanks for your fast response, my friend!

[Steve Johnson]

Update -- my 10-day forecast now has the only day of rain on Thursday, 30% chance of scattered showers, but the day/night temps are expected down to 62/58. Wasn't expecting that. I hope the dual-use functions of my portable greenhouse will be sufficient to keep the rain off and raise the interior daytime temps on the plant bench enough to stave off any rot Thursday. Nothing like a good old-fashioned field test, huh? Nice thing about weather forecasts is the fact that they change, so I'll be keeping an eye on the 10-day as we get closer to Thursday.