Topic: Sweetcorn - not sure what to do

[newspud9]

4 weeks ago I sowed a grid of sweetcorn seeds.  Only 50% have shown (c.2" high) and this is on a random basis across the grid.  Does it matter or do I need to re-sow with new seeds to fill in the gaps...or is too late to do that.

Many thanks for all the replies

[BarriedaleNick]

Thats why I always sow in modules and plant out..
I'd stick some in pots indoors - they should come on quickly and you can fill in the gaps..

[gwynleg]

Hi Newspud - I have had exactly the same problem. Last two years the corn I sowed direct did better by far, so this year I only did that. Of course....this year hardly any germinated and I couldnt get any more of same type. I have resown another type, then moved the first little ones as far away as poss, then put new ones (which I sowed in pots) in the ground. Only just done it and am sure there is time

[newspud9]

Many thanks for these comments.  I'll definitely try the in-door suggestion and hope they catch up with those outside.

[Unwashed]

I wonder that it doesn't depend on the variety.  I was helpfully told this year that the extra-sweet varieties need a little more warmth to germinate than the regular varieties.  I did sow directly one year and it was a complete disaster, but then I don't find sweetcorn the easiest in the greenhouse either as sometimes it gets too leggy and sometimes it gets a check on planting out and takes an age to establish.  What I do find is that it appreciates planting a little deeper than it was in the pot to support it against the wind and then watering carefully so as not to wash the soil away from it.

[Ellen K]

On the packet it usually says something about when sowing in the ground direct, sow 2 seeds per station then (assuming both seeds germinate) thinning to the stronger seedling.  This seems a terrible waste of seed.  If you only want 25 plants, it is not too onerous to raise plants in modules then plant out.  It is not like say peas where you might want 500 plants and even with several seeds per pot, you still need trays and trays of pots.

And yes, they seem to put out additional roots at ground level so planting them a bit deeper certainly does help them stay up in the wind.

[terrier]

I have no trouble getting the plants to grow, I start them off in LARGE pots (5") then when a few inches tall, plant them out. I make a pot shaped hole (using the pot) then drop the plant in, hopefully they will not realize they've been transplanted. My problem is that, although the plants grow on well and get good sized cobs, there's very little seed on the cobs. Happens every year and no matter what I do, still not much corn (on the cob).  ???

[realfood]

Terrier, do you shake the pollen with your hand to make sure you get good pollination?

[plainleaf]

only planting 25 corn plants since here corn is cheap. so unless you go a good amount it is waste space.
now real interesting part would how close you plan on spacing you corn.
1,2,4 plants per foot. 

newspud9 how many plants is 50%

[Jeannine]

Terrier, my first thought about your poor pollination would be the distance you have planted them apart from each other, or you have put them in a row rather than a block. Can you tell us what your planting distances were. You should be able to get good corn, so if we can help  we can try and find the problem for you.It is probably something small and easily fixed.

XX Jeannine

[newspud9]

Hi Plainleaf - have sown 4 rows with 5 seeds in each row, 18" between rows, and 24" between each seed.   

[chriscross1966]

Hi Plainleaf - have sown 4 rows with 5 seeds in each row, 18" between rows, and 24" between each seed.   

Way too far apart really.... I find with modern dwarf varieties you can go at around 8 or 9" between plants in the grid (ie in rows and between rows) and expect one cob per plant.... if yougo wide spaced they might well grow into bigger plants and try to throw a second cob, but by then the pollination will be getting variable adn the cobs won't be well filled.... Try Zucchero from Franchi, you get a lot of seeds in a pack and also try module sowing into 24-drop modules with a toilet roll pushed in and filled with compost..... Sweetcorn doesn't like too much root disturbance, they alwasy sulk a bit after planting out.....

chrisc

[Jeannine]

Newspud, that is way too far apart for good pollinatrion and for Terrier too.

If seeding direct I suggest  4 seeds per foot,1-2 inches deep, on the shallow side for  Supersweets.. I actually prefer starting inside in the UK though but  only thtree weeks before transplanting and in decent sixed pots..Don't soak the seeds and keep them warm.

Ideally they should be thinned to just 8-10 inches apart, and you must have at least 4 rows about 3feet  apart. If only growing a few plants, they are best done in blocks . at about 10 inches all round.

To all who are new to corn.

It is wind pollonated so need to be fairly close if you are only growing a few plants. The roots are shallow so weed around them gently until the corn is 18 inches high then leave it alone, it will be just fine.

Corn is a heavy feeded so add manure, compost or a good general purpose organic fertiliser at planting time, mix it into the soil in the furrow.

If seeding direct you need soil temps of 65%, warmer if growing Supersweets ., they will not germinate under this.

Usual germination for corn is 75% and seed is good for 2 years

Corn is not difficult to grow if it is given what it wants, but I find the UK seed sellers not much help with corn generally which is a real shame as it spoils it or makes it difficulkt for folks.

XX Jeannine

[newspud9]

Chrisc and Jeannine - Thanks..really helpful -  I know I should have asked A4A for help earlier as clearly Ive taken the wrong advice on spacing.  Would it be an option to sow extra seeds evenly spaced between existing rows (nothing ventured etc.)....or just leave and start again next year.

[Jeannine]

If the soil is warm enough, put some in..or start in pots and add to the others in two weeks..they mway mature at different times though. If the soil was soft, I might consider moving them with a good trowel full of soil, but as I can't see the size of your plants I really shouldn't advise you on that. When they start to tassle give them a good shake, or read one of the many articles on the net about hand pollinating them, it isn't difficult and anything to get that male pollen to the waitin g ladies is good.

XX Jeannine

[terrier]

I always set them out in a block but do tend to give them plenty of space (about 18" between plants). I'll try planting them out a bit closer and see if that cures the problem.

[brown thumb]

i dont have any problems with sweetcorn grew sundance [i think it was ]last year planted out 18" apart no special treatment wind only pollinated chicken manure pellets when 1st planted had mostly 2 cobs a missed a ;grain or two on a couple outsiders. a couple had 1or2 black grains ?this year ive tried mini pop planted at 8" apart  so  ill see what happens this year

[Jeannine]

Planting at the correct distance apart will take care of the missing kernels.XX Jeannine

[antipodes]

I did not do any sweetcorn this year but my neighbour did and hers are enormous now, at least 4 feet high. I am tempted but I fear it is too late - I probably have a few Lark seeds left from last year... I worry that they won't have time to mature??

[Jeannine]

If you start them and thern realise you won`t make it, pick them as tiny ones to use in  stir fry.Don`t let them pollinate thoughXX Jeannine