Izhar,

"I was lurking here for quiet long but unable to gather courage asking so many questions... I hope they'll be replied & answered..."

Welcome to our discussions. We are glad to have you. I'll try to answer some of your questions and hopefully others will add their responses and opinions as well.

"1) I start my seeds in pots with up to 30 seedlings in a single pot, transplant them in bed at a distance of 6-12" from each other (Dwarf ones on the lesser side), my question is do this technique lowers the percentage of double blooms? I do get many double ones but less then 50%.. is that normal? (the plants I am referring to are Super Yoga & Magellan)"

Zinnias do resent the disturbance to their roots that occurs when you separate them out from a closely packed planting. I have heard it said (in the Parks seed catalog, for example) that such root disturbance can make them single, but I can't confirm that. However, the root disturbance does "stunt" them and set them back, and I try to avoid that by planting only one or two seeds per small pot. This is a picture of one of my zinnia seedlings in a 3-inch square pot.

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I used to use 2.5-inch square pots, but they weren't big enough for my zinnia seedlings. That particular plant had been "pinched" for branchiness and was about to be re-potted in one of the 5-inch pots behind it. If two or more seeds germinate in a 3-inch pot, I usually snip out the weaker one(s) at the first true leaf stage, to leave only one zinnia plant per pot. I use pointed scissors to cut off the discarded plant at the soil line so as not to disturb any roots. As the zinnia plant grows, it becomes root-bound enough to create a coherent root ball, the same square shape as the inside of the pot. It will hold together on its own and drop out of the pot when it comes time to transplant it into the garden or re-pot it to a bigger pot for continued indoor growth. That avoids disturbance to the roots, and has the advantages of a peat pot without the added expense or delay for the peat pot to disintegrate. I re-use my plastic pots from year to year.

"2) I've grown (in the same fashion as above) Scabious flowered Zinnia bought online from T&M(UK), the percentage of actual scabious flowered ones ware merely 10% of the total, where I went wrong?"

Nothing went wrong. The commercially grown scabious flowered strains are typically only 5% to 20% true to type out of the seed packet. You can improve on that by saving your own seeds. I cull out the many off-type ones and enjoy those that are on type. There is more information on improving your zinnias by saving seeds from selected specimens in the It can be fun to breed your own zinnias message threads here in the Annuals forum.

"3) Is that true that seeds with petal attached (or its part attached) produces double blooms and seeds obtained from the mid of the bloom have a 50-50 chance?"

I hadn't heard that, and haven't run any experiments on that. The petal seeds are more likely to be cross-pollinated (by a bee or by you) while the floret seeds are more likely to be selfed.

"4) How long is the blooming season and how can we increase it? My zinnias planted in spring have an average 5 months period from seed till death, but I have seen zinnia in my area which were blooming before August and are still blooming.."

That is an interesting question, and the answer depends in part on which strain of zinnia you are growing. The Super Yoga strain is bred for cut flower production, and normally produces just the central stem flower which is harvested for sale. The Yogas are bred to be non-branching to focus all of their energy on that main-branch flower. I would guess that they would branch if you pinched the main stem at an early stage, but they aren't bred for continued bloom. The Magellans are an F1 hybrid low-growing strain for extended bloom in a bedding situation, but probably would benefit from dead-heading and would suffer if seedheads were allowed to mature. Many ornamentals suffer if they are allowed to "go to seed", but I think there is a possibility that some zinnias might have the capability to continue putting out new branches with new flowers even though older branches have set mature brown seedheads. I think that is the exception, but I have seen that in several of my home-hybridized zinnias involving a scabious-flowered parent. However, zinnias need warm or hot weather to thrive, and as the days shorten and cool weather approaches, natural conditions tend to end their blooming season.

"5) I use large amount of composted dairy manure as fertilizer tilled in the bed up to 6", a week before transplanting the seedlings and a light sprinkling of 17-17-17 fertilizer every month. This is more or less the same procedure for all of my annual plants, do I need to do differently for zinnias?"

I really can't answer this one. I don't have access to dairy manure or compost, so I rely pretty much exclusively on soluble commercial nutrients like Miracle-Gro and Better-Gro. Zinnias are heavy feeders, so if your zinnias look healthy, they probably like what you are giving them. I do supply some supplemental silicon to my zinnias in a diluted soluble form as potassium silicate. The silicon is supposed to aid in forming strong cell walls and increase disease resistance.

ZM

Zenman,

'm grateful for your replies and they helped me identify some points that I was missing like deadheading, the owners of the long blooming zinnias I was referring, regularly pick the opened up blooms...

Here are the pictures of my last year Super Yoga "Purple" plants, they became tall (around 6') and produced abundant blooms in single, semi-double and fully doubled form:

They were planted 7"-8" apart in mid of April '10, this pic was taken on 9th May '10:
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Started blooming on 16th May:
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These are June pictures, without deadheading they continued to perform till July end:
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