cause of stunted bronze/yellow/purple colored leaves in purple top turnips

[bornagain62511]

I know it's something to do with the soil, but is it a nutrient such as N, P, or K, or other? or PH of the soil? I know I've seen it mentioned before, but can't seem to find it now. what causes the purple top turnips to be very stunted and the leaves turn purple/yellow/bronze in color? And only a few feet away they can appear lush and healthy. thanks!

 

[roymunson]

I believe it's N, but i'll defer to the folks around here who really know.

 

[tdawgcj7]

I have some like this to. I assumed it is either lack of N or maybe I over planted some areas. Last night I broadcast 46-0-0 hoping for rain but now it looks like that might not happen. Hopefully the dew and frost will be good enough over the next couple of days.

 

[Rit]

Too heavy of seeding rate. If you lack N you will have yellow brassicas.

 

[White Birch Farm]

Phosphorous deficiency causes purple brassicas.

You can plant at 10-100x recommended rate and your plants will still look green if you started with adequate fertility levels. If you don't provide enough Nitrogen throughout their life cycle, they will yellow from the bottom up regardless of density.

 

[bornagain62511]

Phosphorous deficiency causes purple brassicas.

You can plant at 10-100x recommended rate and your plants will still look green if you started with adequate fertility levels. If you don't provide enough Nitrogen throughout their life cycle, they will yellow from the bottom up regardless of density.

thanks. I was going to say, seeding rate doesn't seem to make any difference from what I see. same rate over 3 different plots totaling about 3 acres and there are areas where they are lush and green and then pockets here or there (in what appears to be less fertile soils) where they are drastically stunted, and bronze/purple/yellow in color.

 

[White Birch Farm]

thanks.... (in what appears to be less fertile soils) where they are drastically stunted, and bronze/purple/yellow in color.

Check to see if they are in low lyeing areas where you may be getting water ponding. That can result in denitrification. The lack of nitrogen causes stunted growth, including roots, which reduces the plant’s access to P an K, which are relatively immobile in the soil.

 

[bornagain62511]

Check to see if they are in low lyeing areas where you may be getting water ponding. That can result in denitrification. The lack of nitrogen causes stunted growth, including roots, which reduces the plant’s access to P an K, which are relatively immobile in the soil.

yes, I know that is the case in some areas, there are pockets of clay soils and that definitely causes poor water infiltration and tends to cause low soil fertility. other areas are on a side hill and I know that ponding water is not an issue there, and some spots still have the severely stunted bronze/purple/yellow leaves

 

[yoderjac]

yes, I know that is the case in some areas, there are pockets of clay soils and that definitely causes poor water infiltration and tends to cause low soil fertility. other areas are on a side hill and I know that ponding water is not an issue there, and some spots still have the severely stunted bronze/purple/yellow leaves

I don't plant brassica as a stand alone crop. I always plant it as part of a mix and I keep the rates low (say 2 lbs/ac or so for PTT). Different plants will use different nutrients at different rates. This generally means there are more nutrients available for each plant. I find there are some places in my soil (heavy clay) where some plants in the mix will flourish while others will languish. Nature abhors a monoculture. It requires more inputs with no appreciable benefit to deer. With a mix, you don't have to worry as much about rotation. The warning for planting brassica in the same field for more than 2 seasons for disease mitigation purposes is more applicable to farmers planting monocultures. I've planted brassica in the same fields for many consecutive years but because they are part of a mix and the density of brassica is low, the disease risk is low.

I realize this does not directly address your question, but it is good food for thought. It is also good to step back and consider your objectives. I don't know if you have large enough scale to be doing QDM or if you objective is to improve hunting on your land, but in either case ask yourself if what you are seeing is really hurting your objective. We tend to take a little too much from farmers and think of a nice clean farm field with no weeds and fast growing plants as "success". But whether managing for deer or simply trying to influence their movement and patterns to improve hunting, good clean fields may be costing a lot of time and money and not really contributing to the objective. If one is doing QDM and the objective is herd health, the real question is "Was their quality food left in the field when the stress period I planted it for was over?" If not, the answer may be planting more acreage rather than trying to improve yield on a per acre basis. Likewise, if you objective is improving hunting, the question is whether the field influenced deer movement the way you intended and whether a "better" crop would really change that.

Thanks,

Jack

 

[S.T.Fanatic]

As mentioned its phosphorus deficiency.

 

[bornagain62511]

thanks for all the replies everyone