Archives for posts with tag: macronutrients

It would be hard to tell from this blog (because I have posted so few real-time entries since mid-fall, 2014) but I decided not to send any soil out for testing this year (well, technically speaking, last year).

During the previous three seasons (2011, 2012, and 2013), I collected soil samples in late September or October (see October 19, 2013, part 2 for the most recent account) and sent them off to the Rutgers Soil Testing Laboratory. Two weeks after that, the lab sent me via e-mail me a report of our soil’s properties (see February 14, 2014 for discussion of the October, 2013 results).

It was a worthwhile endeavor—information is power, and all that—and we made some adjustments that I am sure were of benefit to the vegetables. Probably the most significant factor that the tests brought to our attention was soil pH. Initially, it was too high and the following year (2012), we added Sulfur to bring it down.

But after that first year, we did not learn anything new. Our soil’s pH has stabilized within the optimal range and both the macro- and micronutrient levels have remained constant. The soil appears to have reached a healthy equilibrium and as a result, there have been no recommendations for change. And as they say, if it ain’t broke, don’t fix it.

This year, the vegetable plants themselves are telling me everything I need to know. Almost all are very happy so the soil must be okay.

After yesterday’s efforts (see June 14, 2015), today’s planting was a walk in the park. Make that a walk in the garden.

We have three varieties of cucumber to plant today: Alibi Pickling Cornichons and Tanja Slicing, same as last year, and Early Fortune, new to our garden. Last year’s varieties have a slight edge (we started them earlier) but all of the seedlings look strong.

To help them along, we sprinkled a tablespoon of bone meal into each hole before setting a seedling on top. The Calcium that should slowly leach into the soil will help the cucumber plants form flowers and will minimize blossom end rot. At least, that’s what they say on the internet.

And they wouldn’t say it if it wasn’t true. Right?

More snow yesterday—a lot more snow—means that it is still too early to be thinking about starting any work on the garden outside.  At this rate of snowstorms, we won’t be digging out until March.

That is just as well because there are still a few items from last year to recap.  Most notably, there are the results of the soil testing that arrived at the end of October (2013) but which I have not had a chance to discuss.

Based on the previous year’s testing, I was not expecting any startling new information for the east and west planters (see October 19, 2013, part 2).  Sure enough, the reports confirmed my expectations.  The all-important pH of the soil remains within the sweet spot (6.20 to 6.80) for vegetable gardens with the east planter at 6.57 and the west planter a tad more acidic at 6.23.

Interestingly, the soil pH of the east planter increased slightly (from 6.31 in 2012) while the soil pH of the west planter decreased (it was 6.78 in 2012).  The soil in the east planter is now squarely within the preferred range but the soil in the west planter is bouncing from endpoint to endpoint.  Both are perfectly fine, however, and we will not have to make pH adjustment to either.

Similarly, the macro- (Ca, K, Mg and P) and micronutrient (B, Cu, Fe, Mn and Zn) concentrations in the east and west planters are close to each other, a result, I think, of at least three factors.  First, we treat the planters identically; neither has received any amendments (other than a top dressing of compost at the beginning of the season) or more fertilizer than the other.

Second, we have been rotating crops back and forth between the planters.  Therefore, their soils have been depleted (or replenished) by more or less the same amount.  Third, the age of the soil in each planter is more than two years.  I assume that given their consistent treatment, both soils are converging on the same steady state.

For the most part, the micronutrient levels in the west planter decreased when compared to last year (i.e., 2012).  This is not too surprising, again considering that we don’t heavily fertilize or otherwise modify our soil during the growing season (I think of it as time smoothing the soil’s rough edges).  Micronutrient levels in the east planter are mostly the same as 2012 (its soil is older and smoother).

What I didn’t expect is that in both planters, the concentration of Calcium increased by almost 50 percent.  We did not add lime, bone meal or any other source of the micronutrient so I have no idea from where the additional Calcium comes.

So much for the well-established planters.  On to the ground level soil, where we planted squash and cucumbers last season.

For starters, the pH of this soil is too high at 7.10 (the soil is slightly alkaline).  We’ve learned from both of the growing seasons prior to last that this can have a very detrimental effect on plant performance.  And I learned from this year’s experiments with seed starting mix that the culprit is probably not the very acidic peat moss, of which the ground level soil is roughly half.  The other half is compost (mainly cow manure) which tends to be more alkaline.

When we dig new pits for the squash and cucumbers this year, we will have to increase the proportion of peat moss to manure and perhaps add some elemental Sulfur to bring the pH down.  Otherwise, the ground soil profile resembles that of the planters.  The macro- and micronutrient concentrations are very close, including—somewhat mysteriously—the high concentration of Calcium.

This is a bit ironic because the summer squash plants experienced a high rate of blossom end rot last season, a condition that is usually associated with Calcium deficiency.  I think this is what the testing lab was alluding to when they called me in the fall (see October 24, 2013).  The testing methods based on acid extraction indicate a high concentration of Calcium but it is not, apparently, in a form that plants can readily use.  I’ll have to look into this one further.

The reports list lots of numbers, not all of them obviously meaningful.  So, what does it all mean?  The bottom line is that our planters’ soil is doing fine and that with minor modification the soil in the ground will come into line as well.  That’s good—if not exciting—news.

After returning home from running errands this afternoon, I was surprised to find a voicemail message from the soil testing laboratory.  This is the third year I’ve sent them soil for analysis and I did nothing different this year compared to the previous two years.  What could the issue be?

I gave the lab a call back and learned that they were concerned that the tests I requested might not be appropriate for our soil.  Based on a brief visual assessment of the soil samples and their labels (“East Planter”, “West Planter”, “Ground Level”), and without checking the type of planting for which the soils would be used (as I had indicated on the back of the soil test questionnaire), the lab scientist thought that perhaps I worked for a mall and was checking the soil from its indoor flower beds.  I’m not sure whether to be flattered (or not).

It turns out that the basic soil tests I commissioned are intended for mineral-based soils and use acids to extract the nutrients of interest.   This method is efficient and quick and yields reliable results for total nutrient content.  However, for soils that have very high concentrations of nutrients in mineral form, the observed values may not represent how much of the nutrients are actually available to plants.  For example, a clod of partially decomposed ore may be rich in iron but spinach still won’t grow well in it.

Alternatively, for compost and other soils rich in organic matter, extraction by water solubility is usually employed.  Apparently, this method takes longer and is somehow more complicated (I infer, because it costs much more) but produces values that are closer to what is readily available to a plant’s roots.  I explained our soil’s situation—it is used for a vegetable garden—its composition—it is a mix of compost, peat moss and native soil—and its history—she looked up the previous years’ reports—and weighing this information, she decided the basic tests would be okay.

The soil scientist said that many people are (and here she groped for a politically appropriate word) enthusiastic about adding organic matter to their soil, by which I believe she meant to imply that they add too much.  Looking at our previous reports, however, she saw that although some of our nutrient levels are high (“above optimum” is the lab’s term), the values are not off the charts.  I think she concluded that the total and available concentrations of nutrients in our soil should not be too different.

Looking more closely at our previous analysis results, she liked that our soil pH was in the green zone (6.20 to 6.80) last year and noticed that in our first year (the east planter only, in 2011), our pH was high.  I reported that based on the report, we adjusted the pH by adding elemental Sulfur and that was probably why we were at the proper acidity by the end of the 2012 season.  She was happy to hear that someone actually followed their recommendations.

The lab will start the soil testing tomorrow and I hope to hear back from them next week.

It’s that time of year again (past time, actually):  Time to send the soil out for testing.

Why is it that time?  Because the growing season is over and the soil is as depleted as it will get this year.  Now is the time to add supplements or nutrients that the soil may need before the new season starts in spring.  And I won’t know what to add without an assessment of what is—or is not—there.  Also, the planters are (almost) bare so it is convenient to take samples.

Testing is becoming less critical for the east planter, which has just completed its third year of service.  Its soil needed adjustment after the first year (to increase its acidity) but received no amendments last year.  We did add a small amount of compost (to bring the soil surface higher) and may do so again this year.  Otherwise, I don’t expect that the soil’s properties have changed much.

Similarly, the soil in the west planter was nearly on the mark in terms of pH and nutrient concentrations, as evidenced by its first soil testing last year (see October 4, 2012).  It received the same treatment as the east planter (a minor infusion of compost) and in conjunction with the solid performance of this year’s crops, is unlikely to need any modifications.

The condition of the newest soil in the garden, the mounds where we planted the squashes and cucumbers, is another matter entirely.  We were not particularly careful in designing this soil and simply mixed together roughly equal parts of compost and peat moss.  It looked right and was good enough but apparently only just so.  While the summer squashes performed adequately (especially the yellow crookneck), the winter squashes and cucumbers did poorly (in fact, only one Kabocha and none of the Delicata squashes reached maturity).

Clearly, there is something missing from (or otherwise not quite right with) this soil.  Testing should help uncover what that is.

As in previous years, for each of the planters and the mounds, I dug soil from four locations, mixed it together and dumped it into a labeled zip-top bag.  I slipped each baggie into a larger one (to contain possible spillage) and packed the three sacks into a box for shipping.  To the box I added the testing lab’s forms (one for each sample) and a check to cover expenses.

Next week, I’ll send them to New Jersey and in another week to 10 days, we should have the results.

Having harvested the last of the string beans (see September 25, 2013), we decided it was time to clear out the vines and start readying the west planter for winter.  Some gardeners would chop up the vines and till them into the soil to decompose and add organic matter (so-called green manure or green fertilizer).  Others might cut the stems off at the ground surface and leave the roots in place, hoping that symbiotic bacteria (if present) would continue to fix Nitrogen in the soil.

But neither of these ideas appeals to me.  Even though the planter is not that big (four feet by 12 feet), turning the soil would be a lot of work.  And anyway, we are following the no-till approach, which moderates decomposition, improves drainage and minimizes weed growth by leaving the soil surface undisturbed.  Somewhat ironically, it also maintains better aeration by eliminating compaction and encouraging the earthworm population.  In fact, our soil is essentially turned over several times a year by an abundance of energetic Lumbricidae.

Leaving the roots in place would require less effort—even less than pulling them out.  However, we do not necessarily have Nitrogen-fixing bacteria and it is not clear that they would have enough time to make a significant contribution to the properties of our soil.  Besides, it is more likely that we have too much Nitrogen rather than not enough (see June 22, 2013), as evidenced by our crops of carrots, beets and radishes which produced more leaves than roots.

Being completely honest, it probably wouldn’t matter if either alternative had a scientific justification because pulling the vines out is more in keeping with my nature.  I have been described as a neatnik and it is a characterization I do not deny.  At a certain level, getting the planter tidied up for its long winter nap is much more important to me than ensuring that the soil has a proper concentration of Nitrogen.  Our soil’s nutrient distribution can be adjusted in other ways and at other times but I have to look at the empty planter all winter long.

What I’ve learned about beets:  First, they need less Nitrogen than flowering plants and relatively low soil pH (i.e., slight acidity).  Our soil is at the high end (6.78) of the preferred range (6.2 to 7.0), based on last fall’s soil report (see October 4, 2012), and I infer that our Nitrogen level is also high (last year’s report recommended adding only nominal amounts).

Second, beet seeds are clustered.  What looks outwardly like a single seed is actually a seedball consisting of three or four seeds held together by an outer layer.  This redundancy helps insure that the plants successfully reproduce—each seedball is three or four times more likely to produce a new plant—but for the gardener, it can be too much of a good thing.  Under favorable conditions, all of the seeds will germinate and if all of the seedlings are left to mature, the result will be plants that are so closely spaced that there is no room for the roots to develop.  Even with careful sowing, therefore, thinning will be required.

Third, while the beet greens can grow quite quickly, the beet roots will sometimes grow very slowly.  This condition arises in part from the higher Nitrogen concentration in the soil—which promotes vegetative growth—and is dependent on temperature as well.  We had a cool spring during which the beet seeds rapidly germinated and produced lovely heads of dark green leaves.

Then, before the roots could catch up, the weather turned warm and the beets’ development slowed.  We kept them well hydrated, so they were not permanently damaged by the heat, but their growth was stunted.  I will do some research into how to minimize the Nitrogen effect (it is not clear what nutrients would promote root growth) and with luck, next year’s beet roots will develop earlier, before the hot weather arrives.

Fourth, beet roots can go a long time unharvested, even in high heat, with no detrimental effects.  We discovered this when we pulled out the first row (see July 28, 2013) and found the beets to be in good condition even though they had been in the ground for months.  It makes sense, botanically:  The roots store solar energy collected during the beets’ first year of growth in order to produce flowers and seeds during their second year.  It makes beets a good choice for busy people.  Unlike more delicate vegetables like tomatoes, which will rot if left unpicked for too long, beets will wait patiently in the garden with no ill effects until their grower is ready for them.

What I already knew about beets:  They are absolutely delicious, especially when roasted, which intensifies their flavor.  And the greens might be more delicious than the roots (they are certainly more nutritious).  Beet greens make a fine addition to salads when they are young and hold up as well as, if not better than, spinach when sautéed.

Lately, I’ve been concerned about the beets.  The first batch has been sitting in the ground since April.  How can they possibly need more time?  Their leaves are a beautiful, dark green color that signifies their high concentration of iron.  But are they still okay after all of this time in the ground, exposed to the summer heat?

To find out, we pulled up the entire first row.  They range in size from marble to baseball and all of them are firm and dry.  They show no signs of rot or other decay.  Also, the growth patterns of the Chioggia (red) and Touchstone Gold beets appear to be essentially identical.

From this, I conclude that any issues (and perhaps that is too strong a word) have to do with the growing conditions and not with the particular beet variety.  Most likely, our soil had too much Nitrogen (which promotes the growth of the greens) to begin with.  Then, when the weather turned hot and the beets were still in the ground, they went into self-preservation mode.

I shouldn’t be surprised that the beets have survived safely in the ground.  Beets are excellent storage vegetables and can be kept for long periods of time if they are protected from light and moisture.  A farmer friend of ours packs his surplus crop in sand-filled wooden crates in which they pass the winter, stacked in the basement of one of his barns.

We won’t keep ours that long.  One night soon, when it is cool enough to run the oven, we will roast them with olive oil and salt and then chop them into a salad with arugula and goat cheese.  The greens, which we carefully cleaned of mulch and soil (but did not wash so as to keep them dry), we will sauté with garlic and onions.

We are still experiencing blossom end rot of the crookneck squash.  It is not affecting every fruit, however, and despite losing two or three potential squash, we were able to harvest two healthy ones.

At the same time, we also picked two of the Cavili zucchini.  These turn out to be a pale green variety (as opposed to the more typical dark green type) and are best picked small (about four inches in length).

Blossom end rot is caused by a deficiency of Calcium in the soil.  The soil in which our squash plants are growing should be rich in minerals but it is new, by which I mean it has not been tested; we do not know its balance of macro- and micronutrients.  It could easily be short on Calcium or perhaps overly acidic.

We have a friend who swears by bone meal.  Whenever she plants a squash or tomato plant, she sprinkles a handful of it into the bottom of the hole.  That way, she knows that the plant will have a ready source of Calcium.  We have rarely done this (based on the results of soil analysis and, admittedly, laziness).

We’ll keep an eye on the squash plants and if the end rot persists, will consider adding Calcium in some form (bone meal is slow so a liquid form may be more efficacious).

This year’s success story, in the early season at least, is the turnips.  They have been happily and exuberantly growing, providing us with tasty bitter greens and piquant roots.  Despite being crowded together, the roots have grown to diameters up to two inches.

The radishes and carrots have been doing moderately well even if they are slower to develop than we would like.  The first two rows of radishes are now mostly gone—eaten—but we are still working on the first row of carrots.  So far, only a few have grown to what I would consider normal size.

At the other end of the scale, the beets have not been performing well at all.  Even those seeded first—longer than two months ago—have not yet produced more than a few small leaves and there has been no enlargement of the roots.  We have been fertilized them monthly but that hasn’t seemed to help.

In fact, it might have hurt.  Doing a little research online, I found that a likely reason the roots haven’t grown is that the beets’ environment is too rich in Nitrogen.  This macronutrient is crucial for flowering plants and promotes the growth of the greens.  And because a plant has only so much energy available to it, what has gone into the leaves has not been available for root development.

That might also explain the slow growth of the radishes and carrots, both of which have towering greens but small roots.  Also, some of the radishes have bolted (gone to flower) which makes sense in a Nitrogen-rich environment.

Talking to our farmer friend, Jay, at the market this morning, we learned further that thinning might be even more critical than we thought.  We’ve been diligently thinning the radishes and turnips, motivated by our predilection for the greens in salads or sautéed as a side dish, but have been less attentive to the carrots.  Their greens are less attractive as a vegetable in their own right.

And I discovered that I had seriously neglected the second row of carrots.  It is sandwiched by two rows of turnips whose bushy greens almost completely obscure them.  I’m not sure I have ever thinned this row and spent a half-hour this afternoon catching up.

Jay also told us that beet seeds are actually seed clusters.  This means that even if they are carefully sown with ample space between them, thinning will still be necessary if and when all of the individual seeds germinate.  There’s no getting around it.