Stop cutting when most of the spears coming up are thinner than a pencil. That is an object, not a calendar date, and it holds in any Louisiana garden. Before the first cut, though, comes a wait: nothing is harvested until year 3, then the season runs four weeks, then six, then eight. Cut spears keep best at 32 to 35°F with their butts standing in water. Soil, water and planting date decide whether you ever get there.
The short answer
A Louisiana asparagus bed is a fifteen-year decision made on one afternoon. Crowns go into 8-inch furrows, nothing is cut until year 3, and then the bed produces for 10 to 15 years. Utah State University Extension, the only authority used on this page, asks one thing of the soil: that it drains. Most soils will do, provided they are well drained. For the full picture of the crop here, start with Growing Asparagus in Louisiana.
The soil USDA lists as representative of the state is the Ruston series, an Ultisol. That is an old, heavily weathered, leached soil, naturally acid and low in nutrients. At the surface it is sandy, with 65 percent sand, 11 percent clay and 24 percent silt. Organic matter is about 1.8 percent, surface pH about 5.5 (slightly acid), and it is well drained. On the single requirement the source sets, Ruston passes easily, because sand sheds water. The cost is a thin larder, so expect to feed a bed on ground like this.
That is the state’s soil, not necessarily yours. Louisiana spans hundreds of soil series, and river bottoms, hill country and any lot a builder has scraped or filled can behave nothing like Ruston. If water stands on your plot a day or more after a hard rain, do not plant there and hope. A heavy soil is an annual nuisance with tomatoes. With asparagus it is a fifteen-year problem you cannot undo, so pick a different spot or build the bed up above the surrounding grade. A soil test through your local extension office gives you your own numbers. The longer discussion is in Will Louisiana Soil Hold an Asparagus Bed for Fifteen Years?
Where the cutting stops each season
Once harvest begins, the end-of-season signal is the spears themselves. When most of what comes up is thinner than a pencil, put the knife away and let the rest grow. Do not convert that into a week number, because a bed that is thriving or struggling will reach it at different times. The furrow gets filled in gradually over the first year, two inches every other month, so four rounds bring an 8-inch furrow level. It is not all backfilled at once. Skip the temptation to sneak a few early spears in the first two seasons. The source gives no harvest before year 3.
Keeping the spears once they are cut
UC Davis Postharvest gives the target as 32 to 35°F (0 to 2°C) with 95 to 100 percent relative humidity. Both edges of that window bite. Above 50°F the spears toughen rapidly, within hours on a warm counter. At about 31°F (30.9°F, to be exact) and below, they freeze, turn water-soaked and collapse on thawing. In a home kitchen, the practical translation of near-saturated air is to stand the cut ends in an inch or so of water, or wrap the butts damp. The cut end loses moisture faster than anything else on the spear.
Will the summer here water it for you?
On paper, mostly yes. The bed wants 1 to 2 inches of water every other week for its first two years, then every three weeks after that. The reference station used here records about 21.3 inches of rain across June, July and August, out of 63.4 inches for the whole year. Here is how to read that against the bed:
- Start with the target. Two inches every other week is the top of the range. Over a 30-day month that works out to about 4 inches at most, and 2 at the low end.
- Compare it with the monthly totals. June averages 7.62 inches, July 6.79 (the driest summer month) and August 6.91. Even July’s total is well past what the bed asks for, so a typical summer should cover the quantity.
- Adjust for sand. The numbers assume rain stays where it falls. On a sandy surface like Ruston’s, an inch passes through within the day. A wet summer can still leave the top foot of a sandy bed dry between storms, which is why a well-drained soil makes the watering question matter more, not less.
- Adjust for how rain arrives. Summer rain here often comes as a single thunderstorm. Much of a heavy downpour runs off rather than soaking in, and hot days drive evaporation hard in the days that follow. An inch in the gauge is not an inch in the root zone.
- Measure your own plot. These are station normals over thirty years, what the region can usually expect, not a forecast. A slope, a tree line or a spot near town can shift them. A cheap rain gauge on the bed settles it.
- Add only the gap. If two weeks pass and the gauge shows less than an inch, supply the difference with a slow soak to bring the total toward the 1 to 2 inches. In a normal summer that may mean little. In a dry spell on sandy ground it may mean every visit.
After the first two seasons, the interval stretches to every three weeks, and a Louisiana summer will carry the bed through most of it. The harder months to watch are the ones outside the three summer ones, which this table of normals does not cover. If you are also tracking what moves into the bed once ferns grow tall, What Eats Asparagus in Louisiana, and When covers that side.
When to put the crowns in
Crowns go in during early spring. In south Louisiana, that cannot be read like a normal planting calendar, because the state barely freezes there. The last spring frost at the reference station falls from around January 18 to February 8, the band where a 32°F freeze has a 30 to 70 percent chance. Those are mean dates, an average of many winters, so treat them as a neighborhood and not a deadline. A 32°F freeze shows up in only 86.8 percent of years at this station. Roughly one winter in seven has no freeze at all, and the freeze window straddles the New Year instead of sitting neatly inside one season.
So in south Louisiana, crowns go in around late January into early February, give or take, once the worst of the cold has passed. The frost date is not the main clock here. Summer heat is, and a bed that is planted late gets less of the cool season before the heat arrives. North Louisiana freezes far more reliably, so its planting date sits later. A specific north Louisiana date is not published in the facts behind this page, so check your own local last-frost figure before you plant.
The alternative is seed. The Utah State source names four varieties and tells you only their sex. Jersey Giant and Jersey Knight are all-male. UC 157 F1 and Purple Passion are male and female. It publishes nothing on flavor, yield or why to prefer one, so any claim that one is better rests on something other than this source, and no nursery is recommended here. A seed start timing is not published either, so follow the packet. Whichever route you take, the clock to the first cut is the same one: planted as crowns or grown from seed, you wait until year 3 before the knife comes out.
Common questions
How do I know it is time to stop cutting?
Watch the spears. When most of them are thinner than a pencil, stop. In the harvest years themselves, plan on four weeks, then six, then eight, rather than cutting until a date on the calendar.
Can I take a few spears before year 3?
No. The source says the bed is not harvested until year 3, and that is firm. A handful in year one or two is not a safe compromise, and the wait buys the 10 to 15 years of production after it.
What temperature should I store cut asparagus at?
Aim for 32 to 35°F with near-saturated air. Above 50°F the spears toughen rapidly, and at about 31°F they freeze and soften badly. Stand the cut ends in water or wrap them damp. A thermometer in the refrigerator tells you more than guessing.
Is Louisiana’s soil good enough for a bed that lasts 10 to 15 years?
The state soil, Ruston, is sandy and well drained, which meets the one requirement the source sets. Your own yard may not be Ruston, and a poorly draining spot is a reason to move the bed or raise it. A soil test gives you your own numbers.