Back in the day, hippies from here to Northern California sprouted their avocado pits and kept the trees in their apartments. If every hippie and their best friend grew them, how hard could it be? Yeah, that’s what I thought.
A few years ago I tried sprouting some, I put a couple pits in dirt and a few more suspended by toothpicks in jars of water. Nothing happened. I blamed it on some sort of treatment the avocados had been through. Now I know better. I think I made two mistakes, no, three. The first mistake was thinking that the radical sprouted from the side of the fruit, like squash seeds, so I planted them on their sides. Wrong. For the best results, the pointed-end should be placed at the top. Some are more subtly shaped than others. The bottom is usually flatter and there is most often a circular marking in a slightly lighter color.
The second mistake was allowing the soil to dry out.
The seeds of avocados, like many tropical trees and fruits are recalcitrant, which means they cannot dry out, or they won’t germinate. Seeds like this cannot be kept outside of the fruit. Sellers who offer recalcitrant seeds often sell them in moist peat, or even pre-germinated.
The third mistake was not waiting long enough. I would say the average germination time has been six weeks.
Planting is soil and suspending in a jars have worked equally well for me. There are advantages and disadvantages to the jar method. An advantage would be the cracking open and emergence of the root is very visible, but the disadvantage is that the jar requires numerous cleanings and water changes during the six weeks. Another disadvantage is the transfer from jar to pot. When I removing a pit from the jar it slipped out of my hand, flew across the room, and landed on the floor, snapping off part of the radical. It was okay and grew normally nevertheless.
The third way to sprout avocado seeds is in the worm bin, the bin provides an excellent balance of conditions favorable for germination. I tossed a couple in my worm bin approximately two weeks later they are beginning to crack. Remember which area of the bin they are in and be careful finding the pits because the roots are very delicate.
Avocados take an average of ten years to reach fruiting size and they will only do so in tropical climates. Avocados fruit best when cross-pollinated with a different cultivar. Because of the dichogamous flowers self-pollination is rare. Darwin was the first to hypothesize that dichogamy was a mechanism to prevent inbreeding. Even though they won’t fruit, for most of us, they are still lovely ornamentals.
Avocados are delicious anyway you choose to eat them, guacamole, Monterey burgers, or even on their own. Unfortunately some people, like my DH, are allergic of avocados. Our little furry friends are also vulnerable to Persin, a fungus-inhibiting toxin in the avocados that can harm pets if consumed in large quantities. People can also be allergic to this substance, but latex fruit allergy is more common.
Latex fruit allergy is triggered by the protein enzyme chitinase. In sensitive people it creates an allergic response by releasing histamine. For people like DH, symptoms set in immediately after ingestion, or up to one hour after ingestion as the body digests the proteins. Symptoms include severe stomach pain, nausea, skin irritation, breathing problems, and in the worst cases, anaphylactic shock. The ripening process, using ethylene gas, also increases the quantity of chitinase in the fruit, possibly increasing the chances for an allergic reaction. Other fruits that can cause the same type of allergic reaction are bananas, mangoes, papayas, and chestnuts. Melons and tomatoes are also suspected. It’s also common to hear of people developing a reaction after increased consumption of certain fruits, for instance I’ve read posts about people becoming violently ill after eating one or more bananas for a number of consecutive days. The good news is, if you are allergic to the triggering fruits the reaction is usually abundantly clear and does not require a diagnoses to confirm.
On Monday I will be posting about growing avocados from seed. Stay tuned!
The story of the Hass Avocado, the modern incarnation of this scandalous fruit, is perhaps even more incredible than its early history. In 1925, after seeing a photos of an avocado tree with dollar bills tied to it, Rudolph Hass a Californian mail carrier with no horticultural background purchased a number of avocado seeds from the, let’s just say, eccentric A.R. Rideout. Rideout scavenged avocado seeds, often from garbage cans, and sold them, as well as avocado plants. Hass was unable to afford seedlings on is 25 cent per hour salary, so he purchased seeds to plant in his small 1 1/2 acre grove that contained a few Fuerte avocado trees. He was instructed by Rideout to plant three seeds per hole, selecting the strongest ones to be the rootstock for grafts of Fuerte trees. Hass hired a professional to graft his trees. After the first attempt all but three of the tree accepted the grafts. The trees were regrafted but again there was one that would not accept the graft. The man advised Hass to let the tree grow because it looked strong and healthy. Ten years after planting his grove, Hass obtained the first patent on a tree for his Hass avocado and gained a following of local buyers who would purchase no other avocados but Hass’. Hass only made $5,000 from the patent because buyers would purchase one plants and then make their own cuttings from it once it was mature. Hass had heart problems the prevented him the enlisting in the Army, he prayed that he would live until the expiration of his patent. He died only several months after the expiration of his 17 year patent. His wife lived in their home for a long time, eating an avocado a day from the trees in their backyard. The original Hass avocado was cut down in 2002, at age 76, after a long battle with root rot. Today as much as 80% of avocados grown in the U.S. are of the Hass Cultivar.
Tomorrow I will be posting about allergies to avocados.
Archaeological evidence of avocados has been found in caves in the Tehuacán area of South-Central Mexico dating to 7,000 B.C. Evidence in the caves showed a gradual increase in the size of the avocado seeds. Researchers proved that avocados were planted and cultivated stream-side beginning by at least 6,500 B.C. The increased fruit size from selective cultivation was slowed by the long-life of the avocado trees and the presence of many smaller fruited trees, but it was nonetheless effective by 900 B.C. Archaeological evidence also showed that the people in nearby Oaxaca did not engage in the same crop improving methods.
Avocado pits were also found at burial sites. The fruits would have been presents for the dead to maintain fertility in the after life.
Scientists have hypothesized that the avocado may have evolved alongside giant mammals that are now extinct. Giant Ground Sloths or Gomphotheres, large elephant like mammals that roamed North and South America, may have eaten the fruits, passing the seeds through their digestive systems intact.
Avocado Persea Americana belongs in the family Lauraceae, which includes sassafras, spicebush, and bay leaves. There are three strains of avocados, Mexican, West Indian and Guatemalan. The Mexican strain, which evolved in tropical highlands is the most cold hardy, surviving temperatures below 20F at maturity. The Foliage of the Mexican strain is reported to have an Anise scent that the others do not. Their fruits also have the highest percentage of oil. Fruit from the West Indian strain have lower percentages of oil and they are the most sensitive to cold. The third group is the Guatemalan Avocado which ripens in the winter, nine to fourteen months after flowering. Avocados from the Mexican strain and the West Indian strain are fast maturing, taking approximately 6 to 8 months to go from flower to fruit. Because of the differing seasons inter-strain hybrids became very import for bridging the gap in the seasonal market. The famous Fuerte cultivar is a naturally occurring cross between the Mexican and Guatemalan avocados.
Avocados are the perfect example of dichogamic protogyny. Which is a fancy way to say that the male and female parts of the flower open at different times, with the female flowers opening first, closing, and then reopening the next day as male flowers. Avocados are harvested before they are ripe because there is a compound in the stem that prevents the fruit from ripening on the tree. In nature avocados would fall off of the tree and ripen on the ground often bruising and effecting the quality of the fruit in the fall. In commercial avocado groves the avocados are picked when they are still green and ripened synthetically using ethylene gas, (the same effect as ripening tomatoes with an apple in a paper bag.) The avocados are harvested using long poles with a v-shaped attachment, the avocado then falls into a cloth sack at the top of the pole to avoid damaging the fruit. Workers in the groves also wear gloves to avoid cutting the skin with their fingernails.
As a fruit avocados have many good properties. They are rich in healthy fats that are proven to reduce bad cholesterol and raise good cholesterol, with regular consumption. On a seven day diet LDL was lowered 22% and HDL was increased 11%. Avocados also have the highest fiber content of any fruit, approximately 6.7g per 100g serving. The fiber consists of 75% insoluble fiber and 25% soluble fiber. Avocados were touted by healthnut and colon/enema freak John Harvey Kellogg (brother of Kellogg Cereal founder W.K. Kellogg) for their health giving benefits in his book, New Diectics, what to Eat and how. As an aside, both of the Kellogg brothers were vegetarians in accordance with their Seventh-Day Adventist faith.
Tomorrow I will be posting about the world’s most famous avocado the Hass cultivar and its accidental incpetion.