mewaldt organics

Selection Strategy :

Every year and for each variety we offer, we select from our working vines those with the best flavor and disease tolerance (especially to curly-top virus). Many of our varieties have over 10 years selection and adaptation to Northern Nevada.   Those plants that survive and produce the best tasting fruit for that variety are carefully chosen for seed collection.  Often, new varieties that we test in our field trials are so sensitive to our disease environment that all individuals of a planting expire within one month of transplanting out. We don’t offer these varieties for sale. 


Curly-top virus (CTV)(among other diseases) is well established and widespread in the Fallon area.  It caused the collapse of a thriving sugar beet industry in the early 1900's and established itself in the local weed community.  Most of our warm season plants are thus exposed to and challenged by CTV each year.   It is spread by small plant sucking insects that act as vectors to transmit the disease from local weeds where it is common to our crops and from plant to plant within the field. These insects travel with the wind and disperse easily. They prefer open fields and monoculture to complex environments.    As the big growers know, poisons don’t help much because infected insects arrive on the winds (probably daily).   Physical barriers, environmental diversity (complexity), and disease resistance (tolerance) seem to be the best strategies for success here in the Lahontan Valley.


Curly-top virus resistant tomatos (CTV resistant tomato).    Korena’s Roma tomato shows very good disease resistance. When compared with Roma VF, approximately twice as many Korena’s Romas typically survive and produce fruit. In 2009,  Lattin Farms planted 800 Korena’s Romas and 500 Roma VF’s side by side in two long rows.  By mid season it was clear that a high percent of the Korena’s Romas were still healthy while over half of the Roma VF’s were dead or dying from CTV or other disease.  Korena's Roma ripens about one week later than Roma VF yet it started out as Roma VF some 15+ years ago.  Korena's Roma ripens later but resists disease better than Roma VF.  We feel that the flavor is better as well.

Our open pollinated Farmsweet Tomato showed some natural disease resistance in our initial trials 15 years ago.  It was almost as successful as the Hybrid Celebrity which was our main season work horse at that time.    After 14 years of selection, our  Farmsweet now outperforms  Celebrity in our fields.

We've been working on the heirloom Cherokee Purple Tomato with some success.  Our strain is very vigorous and is often the first standard sized tomato to ripen each summer.  We still find less than half the plants to be   healthy, green and producing nicely by early September.     From the healthy survivors we select the best tasting for seed stock.  We seem to be making progress in disease resistance.  Flavor was outstanding to start with so we can't verify improvement there.  Most tasters feel that they are still our best flavored tomato.

Shopping Basket
0 items
PayPalPay by Cheques/Check/Other