Fertilizer
2025 Fertilizer Order Form
DEADLINE TO ORDER:
January 11 at 5pm
You must be a member of the San Diego Rose Society to buy fertilizer from our sale.
Click here to join our society!
All info regarding the fertilizer is on this page below the order form. Because the fertilizer is manufactured after the order is placed, no orders will be accepted after January 11, 2026.
You will receive an email confirmation that we received your order.
You can pick up and pay for your FERTILIZER in-person most likely in late January or early February in San Carlos. We will send you an email when the fertilizer has arrived and it’s ready for you to pick up. We do not offer shipping, and orders must be picked up as soon as it gets delivered. Credit cards will be accepted. If you have any questions, please contact us!
SAN DIEGO ROSE SOCIETY FERTILIZER SALE
Rosarians around the world know roses are heavy feeders and benefit from a regular food and water diet throughout the growing year. Our society is committed to helping us provide this optimum diet for our roses. Our fertilizer sale will continue for the 15th year. Here’s our chance to plan ahead to provide our roses with the BEST and LEAST EXPENSIVE nutrients for optimum growth. We don't have to stockpile a lot of product now or pay for the fertilizer way in advance. We lovingly give our roses their spring feeding on FEBRUARY 14 (because we love our roses so much !!)
BioStart 3-4-3 Organic Fertilizer from Growmore is manufactured fresh each year with bone meal, potassium sulfate, humic acid, beneficial bacteria, ecto and endo mycorrhizae. BioStart can be applied at a rate of 2 cups per large bush and 1 cup per small rose bush in the spring. One 50 pound bag contains about 100 cups and will feed about 50 large roses once or 25 roses two times. BioStart may be reapplied in the late summer for a renewed fall bloom. WE ARE THE ONLY RETAIL SOURCE IN THE U.S. FOR THIS AMAZING PRODUCT.
Click here for the product label.
Magnum Rose 8-10-8 Water Soluble Fertilizer is formulated for roses, contains all needed micronutrients and can be applied 1 tablespoon to a gallon of water. One gallon per large rose, ½ gallon per small bush applied every 2 weeks from March 1st to October 15 (that is 18 feedings). One pound = about 32 tablespoons. One 25 pound bag will feed about 25 roses.
Click here for the product label.
Secondary info sheet.
Better Than Fish can be added, 1 tablespoon, to the same gallon of water. One gallon contains about 250 tablespoons, which will feed about 16 roses if applied as above through the growing season.
Click here for the product label.
Seaweed Extract Liquified Natural Kelp provides improved root development, more vigorous growth, increased resistance to diseases & insects and can be added, 1 tablespoon to the above gallon of water. Foliar feeding with Seaweed can really benefit your roses, you may consider applying by a hose-end sprayer several times a year.
Click here for the product label.
Jump Start Plant Tonic brings new life into older plants and gives new plants an extra boost by providing vitamins and minerals needed to encourage new growth and stress resistance, accelerating leaf, stem and root growth. Both Superthrive and Jump Start contain Triacontanol, the “magic hormone”. Jump Start beats Superthrive in performance and price. Apply 1 teaspoon per gallon of water.
Click here for the product label.
ADDITIONAL FERTILIZER
Think about trying some of these products which can be used by adding them to your existing program of applying Magnum and/or Fish, & Seaweed by the gallon to your roses. This would include Biocozyme and Humic Acid. If you currently use/buy any iron product for your roses (I do) Eddha 6% is a good price and can be added to the above several times a year for increasing the deep green leaves. Dexter, from GrowMore talked a lot about the benefits of foliar feeding with Seaweed. Dexter adds the other water solubles to that sprayer to fertilize his garden. Bob Martin had been adding SeaGrow 16 -16- 16 to his feeding program for several years and sweared by the combination of SeaGrow and Seaweed & Magnum Grow. BTW, all these products (and the others we order) retail for lots more than we pay. We try to keep the price low & pass the savings along.
SEA GROW SEAWEED PLANT FOOD 16 – 16 – 16
Application: 1 tsp. - 1 tbsp. per gallon of water
Sea Grow contains a blend of amino acids, botanical seaweed extract, blood meal, carbohydrates, organic carbon, and has a Nitrogen-Phosphate-Potassium ratio (N-P-K) of 16-16-16. It also has yucca extract and micronutrients. One pound =about 32 tablespoons. One 25 pound bag will feed about 25 roses.
Click here for the product label.
Bio-Cozyme Botanical Extract
Application: 1 tsp to 1 Tbsp/gallon
Compatible with all fertilizers, Accelerates NPK Biosynthesis, promotes earlier Flowering, Shorter growing period, Increased bud formation, Increased resistance to plant diseases, Improved appearance and aroma. Aids in achieving full genetic potential.
Click here for the product label.
HUMIC ACID 8% Organic (liquid or granular)
Liquid Application - 1 tsp/gallon every several weeks, for really bad soil - 1 Tbsp/gallon
Humic acid retains nutrients and benefits plant growth. This is particularly good for potted roses because of the nutrient holding qualities of humus.
Gardeners know that humus is wonderful for its effect in helping roses and other plants to grow. How can we help produce more humus in our soil and why is it so beneficial? Humus is a complex substance that results from the action of bacteria and fungi on organic matter. It is recognized as the dark brown to black material in the surface layers of the soil. The particles of humas are microscopic. Amending the soil by thoroughly mixing organic material such as planting mix or compost before planting is the initial way to build humus. In order to continue renewing the soil with humus, add 3-5 inches of organic much each year after pruning your roses. Organic fertilizer also makes a contribution. Many of the properties of humus are due to its negative charge. Think of it like a magnet. The multiple small humus particles with a negative charge hold on to nutrients, most of which have a positive charge. These include nitrogen in the form of ammonium, potassium and iron. Water also has a positive charge and is retained by humus. Humus also has a sponge-like quality that holds water for roots. Roses like a slightly acidic soil with a pH between 6.2 and 6.8. A pH of 7.0 is neutral with levels above this being alkaline and levels below being acidic. Humus plays a major role in stabilizing the pH so it does not become to alkaline or acidic. Humus decays very slowly, at an average rate of 3% per year. It is the largest source of nitrogen reserves in the soil. It consists of about 5% nitrogen and 0.5% sulfur. Humic acid is just one of the many components of humus and consists of organic materials. Most of the time the humic acid is derived from leonardite which is also known as brown coal. Leonardite is a mined product. This, like coal, is the result of prehistoric organic material subjected to prolonged decomposition.
Click here for the product label for liquid.
Click here for the product label for granular.
EDDHA IRON CHELATE 6% Powder-1 lb Application -1 tsp/gal
Fully chelated DTPA iron chelate helps prevent iron chlorosis by maintaining and protecting iron availability in slightly acidic to slightly alkaline soils with a pH of up to 7.5. It prevents iron from binding with other compounds in the soil, allowing it to stay in a form readily available for plant use.
Click here for the product label.
MYCO-GROW
Click here for the product label.
GARDEN MOLASSES
Click here for the product label.
GROW VITE 16-4-2
Click here for the product label.