Diascia is a tender perennial.

Thanks, rhizo. I am not sure exactly what to deadhead and what only has one blooming period and it doesn't help to deadhead. Can you help me there? Thanks, poster of few words. Barb

This is the kind of thing that doesn't have a "rule" to follow. Generally, perennials (whether perennial in your zone or not) are less likely to respond to deadheading by making more flowers. BUT the perennials that tend to be popular "as annuals" usually gain that status because they bloom for a long time, and/or respond well to deadheading.

it doesnt matter what it is.. look at a long branch.. limb.. stem.. whatever ...

and down where there are leaves .... look in the node.. where the leaf attaches to the stem ... if there is a little dormant bud there ... you can cut off all the stuff above.. and that bud will become active ....

now.. if your plant has 10 branches.. lets say.. like a petunia perhaps .... if you had cut one back every week for the last 8 weeks.. you would have rejuvenated the entire plant .... and you would be back to cutting the first one again ... and none of this.. cutting every single flower off ...

this is an easy way to rejuvenate things that have dormant buds.. and if you really look close enough.. a vast majority do ....

when in doubt.. always look for the bud ...

i would never cut anything down.. that did not show buds ... because there is no failsafe ...

see link.. first pic.. on the right side.. i will bet a buck .. having never seen this plant in person.. that there are buds there..

so go take a close inspection of your plant.. and see if you can find them.. and then just selectively start removing some of the older spent stuff .... and then next weekend.. check back on the ones you cut ... and see if the buds below have come alive ... and if so.. then remove more of the older.. until over the next few weeks.. it looks nice again ...

i learned a lot more by experimenting.. than i did anywhere else ...

or as i like to say.. wing it.. lol. . if its really bugging you that much.. just machete it back to 3 inches.. and see what happens ...

ken

Depends what it is.

Pentas, geraniums, heliotrope, ageratum, zinnias = yes (but I only go out there every other week or so due to lack to time)

Vincas, impatiens (regular or New Guinea) = never.

Petunias = one shearing of the plant mid-July.

I have a small number of annuals so deadheading is not a big deal. I kinda enjoy doing it, actually. It is relaxing and makes the plant look nicer afterwards.

of course it does mx ... and i didnt say it would work on everything..

i just said [or meant to say] to look ... study .. learn ...

if you can lop off 20 seed pods in one cut.. rather than 20 snips .. life gets better ....

ken

ps: impatiens root easier than just about anything .... if you need more plants this late in the season.. not sure about NG ... its been decades since i had the various types ... and i think i am confusing begonia in there ... the bulb ones will not root that i know of.. but that wouldnt stop me from trying ....