Monday, March 13, 2017

Fruit tree bloom could be early?

Apricot 'Sungold' Mar 11, 2017
This week's forecast calls for weather not just in the sixties, but reaching into the seventies and possibly even eighty degrees F by the coming weekend. If the warm weather we've been having causes early bloom of fruit trees, blossoms could be caught by freezes.

Apricots are notorious for early bloom. Pictured is Prunus armeniaca 'Sungold' at Denver Botanic Gardens that was in full bloom this past weekend. Apricots may only bear fruit one year out of five (?) here on average because blossoms get caught by freezes in late March and April. The good thing about apricots for a homeowner is that they make a handsome ornamental landscape tree even if there is no fruit crop.

'Sungold' apricot bloom closeup
The bigger concern is with our other fruit tree species that may start to break bud as chilling requirements are met and temperatures allow them to resume growth. They need moisture to do this as well.

Along with cold temperatures, moisture has been lacking so far this spring. Watering your fruit trees is likely a good idea on the Front Range if the current dry conditions continue. Thankfully, our mountain snowpack is now around 130% of normal so we have water to irrigate.

Photo credit: Both apricot photos Carl Wilson

Friday, January 27, 2017

New Vegetables for 2017

'Patio Choice Yellow' tomato
Got small spaces? 'Patio Choice Yellow' F1 tomato may be right for you.

An All-America Selections winner, this tomato is a compact, determinate plant growing only 15 to 18 inches tall. It's the perfect size for container growing on a balcony or other small space.

Vines can bear 100 fruit and begin bearing in only 65 days from sowing seed.  The 1 inch bright yellow fruit are mildly sweet with a touch of acid.

'Antares' F1 bulb fennel
Why not try something new in your garden this year? 'Antares' F1 fennel not only produces an edible bulb, it's fine textured fronds are very ornamental in the garden. You can grow the plant for its culinary seed and it is also a favorite food for swallowtail butterflies and other pollinators.

The bulbs are said to have an improved, almost sweet licorice-anise flavor as compared to other market varieties. It is also a week slower to bolt.

Fennel is a warm season vegetable that will grow bulbs 4 to 5 inches in diameter and foliage 24 inches tall. Grow in rows 6 inches apart with 24 inches between rows. The plant is ready to harvest 68 days from sowing seed or 58 days from transplanting. Plants can be grown in a container if desired.

Photo credit -  All-America Selections

Tuesday, October 4, 2016

Pumpkins for many purposes

Pumpkins grow in a south-
facing bed with strawberries
(Photo credit Carl Wilson)
Pumpkins, Cucurbita pepo, are easy to grow if you have room. A 10 to 15 foot vine spread is typical although there are a few bush type varieties (see Wee-B-Little below). Plant from transplants as soon as the weather is warm because they require 90 to 120 days to harvest.

In the photo a home entry walkway is bordered with a bed used to grow strawberries in early summer and pumpkins for fall. A few tulips come through in spring to add some color to this garden. Talk about making good use of garden space for many purposes!

You may want to grow pumpkins for one or many uses including decoration, cooking and baking. Fruit size may also be important to you. Know that there are pumpkins to fit most any requirement.

Baby Bear 
Baby Bear is a small, 3.5 to 5.5 inch pumpkin weighing in at 1.5 to 2 pounds. It is just the right size to use for decoration and sweet so it can be used for pie fillings.

Hijinks is slightly larger at 7.5 inch diameter and 7 to 9 pounds. It's blocky round shape makes it ideal for carving.

Cinderella's Carriage
The pink-red color of Cinderella's Carriage variety will fulfill the fairy-tale dreams of any child. Vines grow flat fruit up to 18 inches round and weighing up to 20 pounds.  The yellow flesh is mildly sweet and ideal for soups and baking.

Pepitas is a new 2016 twist in pumpkins with it's yellow-orange fruit striped with green. Twelve inch round fruit weigh in at about 12 pounds. The hulless seeds can be slow roasted for nutritious snacks and yellow flesh eaten or baked.

Finally, if you have 6 to 8 feet of space try growing Wee-B-Little, a bush type. Fruit is 3.5 inch in diameter and skin a smooth, deep orange. It can be used for decoration, crafts and makes a tasty vegetable when baked as a mature winter squash.

All five varieties mentioned are All-America Selections winners that should grow well in the Intermountain West.

Photo credit - All-America Selections unless noted

Friday, September 9, 2016

Good year for fruit on the Front Range

It is often said that spring freezes are the biggest danger to fruit growing. This year many areas of the Front Range were spared freezes at flowering resulting in generally good fruit set.

Another reason for heavy fruiting is that stored energy is high because many trees bore little fruit in 2015. A warm fall in 2014 didn't allow many trees to prepare for cold weather. Sudden subzero temperatures in early November 2014 following the warm fall caused freeze injury to a variety of plant tissues some affecting flower buds. That and usual spring freezes resulted in generally light crops in 2015. Not using energy on fruit last year left trees with ample stores to carry a large crop to harvest this year.

It will be a good year for gleaning to donate to food pantries but do check with landowners first.

This street-side apple in Louisville, Colorado also illustrates another point. Trees sited in heavily irrigated and fertilized lawns often respond with excessive vigor. They show lots of shoot growth and poor fruiting. This apple in an obviously sparsely irrigated and little fertilized area is bearing a nice crop as pictured in the close-up above.

The take away message is that mature fruit trees do better on less water and fertilizer than is applied to grow medium to high quality bluegrass lawns. A separate non-lawn site for growing fruit trees is a better growing situation for producing fruit rather than leaves.

Photo credit: Both apple tree photos credit Carl Wilson

Friday, September 2, 2016

Varieties Adapted to Front Range Colorado

Amy's Apricot tomato
Cherry tomatoes are convenient for many people and golden cherry tomatoes have been of interest. Sun Gold is one that seems to do well in Denver and has become popular.

This year I tried another heirloom, Amy's Apricot, that did equally as well and has excellent flavor. An indeterminate type like Sun Gold, the only concern for some may be that Amy's Apricot is is 10 days later at 74 days versus Sun Gold at 55 to 65 days. carries Amy's Apricot seed.

Caroline fall bearing raspberry
Switching to small fruit, your fall bearing raspberries should be yielding well by now. If you are still growing Heritage red raspberry, consider switching to an earlier bearing variety when you pull out plants (generally necessary due to virus buildup after 10 years or so).

Newer fall raspberry varieties such as Caroline, Jaclyn and Autumn Britten bear fruit 2 weeks earlier. Late bearing Heritage has always been problematic with coming into bearing when frost danger may threaten in mid to late September.

Fall bearing raspberries are generally recommended in Colorado because they bear on first year canes; you don't need to worry about winter-kill of canes or buds as you do with summer bearing types that don't bear until their second year. Fall bearing types are easy for pruning too because canes are cut to the ground every year in December/January and regrow to produce a crop the next season.

Photo credit: Both photos credit Carl Wilson

Thursday, April 28, 2016

Prospects for Fruit this Year in Denver

The 2015-2016 winter in Denver was unusually mild for fruit tree flower bud survival with only two days of zero degrees F (December 17 and 28) and no temperatures below zero (National Weather Service DIA records).

February 2016 brought enough warm days that fruit trees with a low chill requirement and low growing degree hours to reach bloom such as apricots and peaches were in flower by mid March.

Apricot in bud March 5
Apricot in flower Mar 19
with snow on branch

March brought fifteen days with minimum temperatures 28 degrees F or below. Overnight lows were 20 degrees F on March 19th and 10 degrees F on March 24. As a rough guide, 28 degrees F is the low temperature where many flower buds showing color or in bloom can be damaged. Prospects for apricot and peach fruit this year are likely poor.

Apple blossoms April 24
April has brought warmer nights. Since April 1st when the overnight low was 25 degrees F, the minimum temperature has not dropped to 28 degrees F.

This means that late blooming fruit such as apple and pear, and even fruit that bloomed slightly earlier such as sour cherry and plum may have fruit this year. Note that the specific location of fruit trees, localized overnight minimum temperatures, health of trees and amount of bee pollination activity are some of the factors that will affect your prospects to develop blossoms, set and grow fruit.

Photo credit: All photos credit Carl Wilson