[Guzzik]

Hi peoples.  Ok, have had the allotment for a year and a month.  Forgetting the bad weather/growing etc due to no rain/frost/ice etc, why should seedlings only grow on one side of my plot?  Let me expand a bit.

The soil is a bit dead.  Did a Ph and Potash/Phosphate check last year and the Ph was brill, the rest were VERY low indeed.  Dug in a pile of "muck", not very good muck but, muck just the same.  In some places seeds came up with no problems, sometimes one row of seed came up and the next row failed or only came up for half the row length.  It was noticed that anything grown in cells then planted out grew well though.  If one looks along the length of the plot ones sees that all the growth is on the LEFT hand side almost to the middle with little or nothing on the right hand side.

A few days a go I sowed cylindrical and Bolthardy Beetroot seed and Parmex carrot. Three rows of Parmex and two of Bolthardy and two of the cylindrical beetroot seeds.

One row of Boltardy have come up, the other has not, one row of cylindrical has just about come up, the other is patchy.  The Parmex has two thirds of a row and next to nothing sprouting on the other two rows.  All these rows are in an area 5 metres long by 5 metres wide so, they are more or less in the same place (ish).

Any clues or ideas would be wonderful!

[Yorkie]

Poor drainage?

What was there before, what did you discover whilst clearing the plot?  e.g. any contaminants?

[Shop Keep]

Were the seeds you used still in date?

[JayG]

If I understand you right and you are saying that established seedlings grow well in all parts of your plot then there can't be anything seriously wrong with the soil overall.

There must be a clue somewhere; you need Sherlock Holmes-like observation and deduction skills to work it out!

My immediate thoughts would be that you could have (very) localised areas which are either wetter or more free-draining than the others, which could affect germination rates.

Is it possible that the "bad" areas are nearer possible daytime retreats for slugs and snails which are nobbling your seedlings at night before you even get to see them?

Birds can also take a liking to various seedlings and often seem to attack them in a quite random way (netting all your seed-beds would eliminate this one!)

[Guzzik]

Poor drainage?

What was there before, what did you discover whilst clearing the plot?  e.g. any contaminants?

Nope, nice three foot ish of sandy soil on top of a few billion tons of gravel.  No contaminants seen.  Plot was used by lady and her son to teach him gardening, everything grown was grown rather haphazardly.  We dug out (no joke) nigh on 90lb of self seeded spuds, plus onions and marrows.  She also sowed THREE rows of Poppies and left them for three years, you tell me about the seeds coming up now:)

Seesm the lady was good at sowing seeds then leavingthem to seed again type thing, she also never put anything back into the soil in the time she had the plot.  I am at a loss.  I have been in gardening/green keeping since 1970 but have never seen this before.  All seeds were at the same depth of row, all were watered the same and had the same BFB meal put down and worked in just before seed sowing.  I don't think the manure we put in last year had that weed killer on it.  I use the term "manure" rather loosley as it was more straw and hay than pooh!

So, what now?  I am going to do another pile of soil tests next week to see if any goodness has gone in from the muck spreading done.

[Yorkie]

So, what now?  I am going to do another pile of soil tests next week to see if any goodness has gone in from the muck spreading done.

I wouldn't expect the manure to make a significant difference to the nutrient levels, though.  It is generally nutrient-poor and its main benefit is to improve soil structure.

[Guzzik]

If I understand you right and you are saying that established seedlings grow well in all parts of your plot then there can't be anything seriously wrong with the soil overall.

My immediate thoughts would be that you could have (very) localised areas which are either wetter or more free-draining than the others, which could affect germination rates.

Is it possible that the "bad" areas are nearer possible daytime retreats for slugs and snails which are nobbling your seedlings at night before you even get to see them?

None of the areas have bad drainage.  And none are near slug areas etc.  What gets me is that the weeds grow like heck on the side where the veg seedlings don't.

[Guzzik]

Were the seeds you used still in date?

All seeds used were well in date.

[ex-cavator]

Nothing like a hedge / former hedge or trees or suchlike down one side? Or a ditch that might affect drainage across the plot? No underground structures or former excavations that might have affected drainage? Clutching at straws, here 

[zazen999]

a - can we have a photo showing the plot?
b - what are the weeds that are growing on each side; are they the same or totally different and what are they? Do the annual seeds [poppies etc] germinate ok on the bad side?]
c - when you put seedlings in, do they grow as well as the other side?
d - is the depth of sand over the top of the gravel the same depth as the other side?
e - have you tried digging out a meter square in each side, and swapping the soil itself over and seeing whether things germinate?
f - where is the nearest watercourse?
g - does the soil smell of anything other than soil - anything soapy, or chemically [ I know you said no contaminants but you'd be surprised]
h - if you put a scoop of soil from each side into a jam jar, fill with water and shake and leave for 24 hours - do you have the same soil profile in each container? Is the water bubbly at all after you have shaken it? Or in any way oily?
i - do the annual wild seeds germinate the same, or at a lower [or higher rate]?

[Soils engineer for 14 years; without seeing it or coming to visit it's the first few things that are coming to mind]....so the jam jar test, smell it, test the actual depth and do all these in at least 3 different places on each side and put the results on here and I'll have another think overnight.

[fatcat1955]

Easiest way to check the drainage is to did a hole 2ft wide x 2ft wide x 2ft deep then try to fill it with water. If you fill it easily then it's a drainage problem, if you struggle to fill it or can't fill it thens drainage is ok. What happens if you put transplanted seedlings in those areas, if they are ok then there the soil seems ok. What is the distance between the rows of ok and not ok seedlings?

[aelf]

I would think that as volunteer spuds and poppies have been doing ok, that is encouraging, less likely to be contaminants in the soil.

[Guzzik]

a - can we have a photo showing the plot?

Yep, when I do one tomorrow.

b - what are the weeds that are growing on each side; are they the same or totally different and what are they? Do the annual seeds [poppies etc] germinate ok on the bad side?]

Groundsel, milk thistles, couch, plaintain, grass, docks and a few others.  Yes, all weeds and poppy seeds and self seeding potatos grow perfectly well on the "bad side".

c - when you put seedlings in, do they grow as well as the other side?
Seedlings grow as to expected on the "good" side but do not even germinate on the "bad" side.

d - is the depth of sand over the top of the gravel the same depth as the other side?

There is no "sand" over the gravel layer, just sandy soil to a depth of a good three foot, obviously, the deeper one goes down, the more gravel is in the "soil".

e - have you tried digging out a meter square in each side, and swapping the soil itself over and seeing whether things germinate?

Nope, not done that.

f - where is the nearest watercourse?

About half mile as the "crow flies", it is called The River Frome:)

g - does the soil smell of anything other than soil - anything soapy, or chemically [ I know you said no contaminants but you'd be surprised]

Nope, soil smells like soil should.

h - if you put a scoop of soil from each side into a jam jar, fill with water and shake and leave for 24 hours - do you have the same soil profile in each container? Is the water bubbly at all after you have shaken it? Or in any way oily?

Everything is normal.

i - do the annual wild seeds germinate the same, or at a lower [or higher rate]?

Good question.  Higher rate.  Infact, Louise (the wife) says 80% higher rate.

[Soils engineer for 14 years; without seeing it or coming to visit it's the first few things that are coming to mind]....so the jam jar test, smell it, test the actual depth and do all these in at least 3 different places on each side and put the results on here and I'll have another think overnight.

I am also going to do a full soil test at three differing depths.  The first tests I did last winter showed virtually no Phosphates, potash etc.  Ph is good at 6.5 to 7.5 over the whole plot.

This is why I cannot suss why seeds are not germinating properly.  By the way.  Thank all of you for your input on this.  I am used to getting an 85ish% seed germination rate with veg seeds so this is a bit "huh!", to me

[zazen999]

After your responses; I'd dig out a meter square each side and make a seed bed and try a line of : radish, onions, brassicas, lettuce and tomatoes; just to look at germination rates and see if there is a difference, as well as those pH and nutrient levels.

Very odd!

[RichardA]

I find if lime is in excess as happened when I was given a lot of spent mushroom compost and used it a bit heavily then germination is very erratic so pH in one spot differing from another might be due to ph differences. Also test your seed on "multipurpose compost to be sure it is not health or age or storage of seeds showing as a germination problem.
When I planted out plants such as BB or brassicas or sweet corn the excessive mushroom compost made no difference at all. Only seeds affected
So just a thought for you - could be heavy use of lime in the past or natural pH or run off bringing in a pH change (eg off a concrete slab or path) making the difference
R