Sowing Chickpeas: Soil Temperature, Depth and Spacing

Work backwards from the dry weeks, not forwards from the frost

Almost every other legume is sown by counting forward from the last frost. Chickpeas are different, because the crop is not finished when the pods fill, it is finished when the whole plant has dried down in the field. That last stage takes three to four weeks and it needs dry, sunny, breezy weather. Rain during it splits seed coats, sprouts seed inside the pod and lets pod rots in, and a crop that looked perfect can be lost in a wet fortnight.

So the useful question at sowing time is: when are the driest weeks of my year, and does ninety to a hundred and twenty days from now land on them? In a climate with a dry late summer, sow as early as the soil allows so that ripening falls before the autumn rains. In a climate with wet summers and dry autumns, sow later. In a mild-winter climate with wet summers, chickpeas are a cool-season crop sown at the start of the dry half of the year, exactly as they are grown in their native range.

The plants themselves are more forgiving of cold than the calendar suggests. Young chickpeas take light frost down to about 28F (minus 2C) without lasting damage, so an early sowing is rarely lost to a late cold snap. What kills an early sowing is cold wet soil, not cold air.

Chickpea seed swells and splits easily. Do not pre-soak it and do not sow into saturated ground. Both cause the seed coat to rupture and the seedling to die before it reaches the surface.

Depth, spacing and how wide to leave the row

Sow two inches (5 cm) deep, which is deeper than most gardeners expect from a seed this size. The shallow one-inch sowing that suits peas gives chickpeas a poor start: the seedling emerges with a weak anchor, the taproot is slow to drive down, and dry surface soil stalls germination halfway. Two inches puts the seed into moisture that will still be there in ten days.

Space seeds four to six inches (10 to 15 cm) apart in the row, with rows eighteen to twenty-four inches (45 to 60 cm) apart. That looks generous for a plant that only reaches eighteen to twenty-four inches (45 to 60 cm) tall, and the temptation is always to crowd it. Resist that. A chickpea bush spreads as wide as it is tall, and the single most effective thing you can do against ascochyta blight is to leave enough air between plants that the foliage dries within an hour of dew burning off.

There is no need to thin afterwards, so sow at final spacing plus about a fifth for losses. Chickpeas transplant badly because of the taproot, so gapping up with spare plants from a module tray only works if you do it in the first two weeks and lift the whole plug undisturbed.

1. Check the soil temperature, not the calendar Push a soil thermometer two inches down mid-morning on three consecutive days. You want 50F (10C) or above on all three before you sow.
2. Loosen deep, level the surface Fork the bed to a spade's depth so the taproot has somewhere to go, then rake level. Do not add nitrogen fertilizer or fresh manure.
3. Draw a two-inch drill Take a drill two inches (5 cm) deep with the corner of a hoe. On light soil go slightly deeper; on heavy soil stay at two inches.
4. Space seeds four to six inches apart Place seed by hand rather than trickling it. Sowing more thickly and thinning later wastes seed and leaves the survivors crowded at the base.
5. Cover, firm gently, and leave it alone Backfill and press down lightly with the back of the rake. Water once if the soil is dry, then do not water again until seedlings show.

Inoculant, and why you leave the nitrogen out

Chickpeas fix their own nitrogen from the air through nodules on the roots, and once nodulation is established a healthy crop needs no nitrogen feeding at all. Adding it does active harm: a nitrogen-rich bed produces a big soft leafy plant that flowers late, sets fewer pods, lodges in the first storm and holds moisture in the canopy where blight starts.

The bacterium chickpeas partner with is specific to them, and it is not the same one that nodulates peas, beans or clover. If chickpeas have never grown in your soil, the bacterium is very likely absent, and the first crop will nodulate poorly and look pale and stunted from about the fourth week even in decent ground. A chickpea-specific inoculant dusted onto damp seed immediately before sowing solves this, and once you have grown a crop the organism usually persists in that soil for several years.

Phosphorus and potassium are a different matter. A modest dressing of compost worked in before sowing, or a balanced low-nitrogen fertilizer, supports pod fill without producing the leafy growth that nitrogen causes. On soil that has grown vegetables well for years, compost alone is enough.

Slow or patchy emergence

Ten to fourteen days is normal in cool soil, and gardeners who are used to peas up in five days often disturb the row to check, which breaks the emerging shoots. Leave it. If nothing has appeared after eighteen days, dig up two or three seeds and look at them rather than resowing blind.

A seed that is swollen, soft and gray has rotted, which means the soil was too cold or too wet. A seed that is intact and hard has not taken up water, which means the bed was too dry. A seed with a split coat and a dead white shoot took up water too fast, which is what pre-soaking or heavy watering after sowing does. Each of those points at a different fix, and none of them is solved by simply sowing more seed into the same conditions.

Birds and mice take chickpea seed readily, and mice in particular will work along a drill and take every seed in it. If a whole row fails and there is no seed left to find, that is what happened, and the answer is netting or a cloche over the row until the seedlings are up.

What to write down at sowing

The sowing record for chickpeas earns its keep more than for most crops, because the crop is judged on whether the harvest lined up with dry weather, and you can only judge that in hindsight. Write down the sowing date, the soil temperature you measured, and the row spacing you actually used rather than the one you intended.

Also note where the row is, precisely enough to find it next year. Chickpeas should not follow other legumes on the same ground for three or four years because of soil-borne root rots, and a sketch of the bed is worth more than a memory of it.